answers (anticipation guide and lesson 7-1) · chapter 7 a1 glencoe algebra 2 answers answers...

26
Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 Glencoe Algebra 2 NAME ______________________________________________ DATE ____________ PERIOD _____ 7 Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. Anticipation Guide Radical Equations Chapter Resources Before you begin Chapter 7 Read each statement. Decide whether you Agree (A) or Disagree (D) with the statement. Write A or D in the first column OR if you are not sure whether you agree or disagree, write NS (Not Sure). After you complete Chapter 7 Reread each statement and complete the last column by entering an A or a D. Did any of your opinions about the statements change from the first column? For those statements that you mark with a D, use a piece of paper to write an example of why you disagree. STEP 2 STEP 1 STEP 2 A, D, or NS Statement A or D 1. Functions can be added or subtracted in the same way as polynomials. A 2. A composition of functions, f [g(x)], is found by multiplying f(x) by g(x). D 3. The inverse of a function is the set of ordered pairs obtained by taking the opposite of each coordinate in the original D ordered pairs. 4. Two functions are inverses of each other only if their compositions are the identity function. A 5. The domain of y (x 3 ) would be x 3. A 6. The principal root of any n th root is always positive. D 7. The radical expression 34 is in simplest form. D 8. 4 3 and 4 3 are conjugates of each other. A 9. 5 is the same as 2 5 3 . D 10. To solve an equation containing the square root of the variable, square both sides of the equation. A 2 3 m m 3 Lesson 7-1 Chapter 7 5 Glencoe Algebra 2 NAME ______________________________________________ DATE ____________ PERIOD _____ 7-1 Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc. Lesson Reading Guide Operations on Functions Get Ready for the Lesson Read the introduction to Lesson 7-1 in your textbook. Describe two ways to calculate Ms. Coffmon’s profit from the sale of 50 birdhouses. (Do not actually calculate her profit.) Sample answer: 1. Find the revenue by substituting 50 for x in the expression 125x. Next, find the cost by substituting 50 for x in the expression 65x 5400. Finally, subtract the cost from the revenue to find the profit. 2. Form the profit function p(x) r (x) c(x) 125x (65x 5400) 60x 5400. Substitute 50 for x in the expression 60x 5400. Read the Lesson 1. Determine whether each statement is true or false. (Remember that true means always true.) a. If f and g are polynomial functions, then f g is a polynomial function. true b. If f and g are polynomial functions, then is a polynomial function. false c. If f and g are polynomial functions, the domain of the function f g is the set of all real numbers. true d. If f (x) 3x 2 and g(x) x 4, the domain of the function is the set of all real numbers. false e. If f and g are polynomial functions, then ( f g)(x) ( g f )(x). false f. If f and g are polynomial functions, then ( f g)(x) ( g f )(x). true 2. Let f (x) 2x 5 and g(x) x 2 1. a. Explain in words how you would find ( f g)(3). (Do not actually do any calculations.) Sample answer: Square 3 and add 1.Take the number you get, multiply it by 2, and subtract 5. b. Explain in words how you would find ( g f )(3). (Do not actually do any calculations.) Sample answer: Multiply 3 by 2 and subtract 5.Take the number you get, square it, and add 1. Remember What You Learned 3. Some students have trouble remembering the correct order in which to apply the two original functions when evaluating a composite function. Write three sentences, each of which explains how to do this in a slightly different way. (Hint: Use the word closest in the first sentence, the words inside and outside in the second, and the words left and right in the third.) Sample answer: 1. The function that is written closest to the variable is applied first. 2. Work from the inside to the outside. 3. Work from right to left. f g f g

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Page 1: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A1 Glencoe Algebra 2

An

swer

s

Answers (Anticipation Guide and Lesson 7-1)

STEP

1

Cha

pter

73

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Ant

icip

atio

n G

uide

Rad

ical

Eq

uat

ion

s

Chapter Resources

Bef

ore

you

beg

in C

ha

pte

r 7

•R

ead

each

sta

tem

ent.

•D

ecid

e w

het

her

you

Agr

ee (

A)

or D

isag

ree

(D)

wit

h t

he

stat

emen

t.

•W

rite

Aor

D i

n t

he

firs

t co

lum

n O

R i

f yo

u a

re n

ot s

ure

wh

eth

er y

ou a

gree

or

disa

gree

,w

rite

NS

(N

ot S

ure

).

Aft

er y

ou c

omp

lete

Ch

ap

ter

7

•R

erea

d ea

ch s

tate

men

t an

d co

mpl

ete

the

last

col

um

n b

y en

teri

ng

an A

or a

D.

•D

id a

ny

of y

our

opin

ion

s ab

out

the

stat

emen

ts c

han

ge f

rom

th

e fi

rst

colu

mn

?

•F

or t

hos

e st

atem

ents

th

at y

ou m

ark

wit

h a

D, u

se a

pie

ce o

f pa

per

to w

rite

an

exa

mpl

e of

wh

y yo

u d

isag

ree.

STEP

2

ST

EP

1S

TE

P 2

A,D

,or

NS

Sta

tem

ent

A o

r D

1.F

un

ctio

ns

can

be

adde

d or

su

btra

cted

in

th

e sa

me

way

as

poly

nom

ials

.A

2.A

com

posi

tion

of

fun

ctio

ns,

f[g

(x)]

, is

fou

nd

by m

ult

iply

ing

f(x)

by

g(x)

.D

3.T

he

inve

rse

of a

fu

nct

ion

is

the

set

of o

rder

ed p

airs

obt

ain

ed

by t

akin

g th

e op

posi

te o

f ea

ch c

oord

inat

e in

th

e or

igin

al

Dor

dere

d pa

irs.

4.Tw

o fu

nct

ion

s ar

e in

vers

es o

f ea

ch o

ther

on

ly i

f th

eir

com

posi

tion

s ar

e th

e id

enti

ty f

un

ctio

n.

A

5.T

he

dom

ain

of

y�

�(x

�3

�)�

wou

ld b

e x

�3.

A6.

Th

e pr

inci

pal

root

of

any

nth

roo

t is

alw

ays

posi

tive

. D

7.T

he

radi

cal

expr

essi

on�34�

is i

n s

impl

est

form

.D

8.4

��

3�an

d 4

��

3�ar

e co

nju

gate

s of

eac

h o

ther

.A

9.5

is t

he

sam

e as

�253 �

.D

10.

To s

olve

an

equ

atio

n c

onta

inin

g th

e sq

uar

e ro

ot o

f th

e va

riab

le, s

quar

e bo

th s

ides

of

the

equ

atio

n.

A

2 � 3

m � m3

Lesson 7-1

Cha

pter

75

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Less

on R

eadi

ng G

uide

Op

erat

ion

s o

n F

un

ctio

ns

Get

Rea

dy

for

the

Less

on

Rea

d t

he

intr

odu

ctio

n t

o L

esso

n 7

-1 i

n y

our

text

boo

k.

Des

crib

e tw

o w

ays

to c

alcu

late

Ms.

Cof

fmon

’s p

rofi

t fr

om t

he

sale

of

50 b

irdh

ouse

s. (

Do

not

act

ual

ly c

alcu

late

her

pro

fit.

)S

amp

le a

nsw

er:

1.F

ind

th

e re

ven

ue

by s

ub

stit

uti

ng

50

for

xin

th

e ex

pre

ssio

n 1

25x.

Nex

t,fi

nd

th

e co

st b

y su

bst

itu

tin

g 5

0 fo

r x

in t

he

exp

ress

ion

65x

�54

00.

Fin

ally

,su

btr

act

the

cost

fro

m t

he

reve

nu

e to

fin

d t

he

pro

fit.

2.F

orm

th

e p

rofi

t fu

nct

ion

p(x

) �

r(x

) �

c(x

) �

125x

�(6

5x�

5400

) �

60x

�54

00.S

ub

stit

ute

50

for

xin

th

e ex

pre

ssio

n 6

0x�

5400

.

Rea

d t

he

Less

on

1.D

eter

min

e w

het

her

eac

h s

tate

men

t is

tru

eor

fal

se. (

Rem

embe

r th

at t

rue

mea

ns

alw

ays

tru

e.)

a.If

fan

d g

are

poly

nom

ial

fun

ctio

ns,

th

en f

�g

is a

pol

ynom

ial

fun

ctio

n.

tru

e

b.

If f

and

gar

e po

lyn

omia

l fu

nct

ion

s, t

hen

is

a p

olyn

omia

l fu

nct

ion

.fa

lse

c.If

fan

d g

are

poly

nom

ial

fun

ctio

ns,

th

e do

mai

n o

f th

e fu

nct

ion

f�

gis

th

e se

t of

all

real

nu

mbe

rs.

tru

e

d.

If f

(x)

�3x

�2

and

g(x)

�x

�4,

th

e do

mai

n o

f th

e fu

nct

ion

is

th

e se

t of

all

rea

ln

um

bers

.fa

lse

e.If

fan

d g

are

poly

nom

ial

fun

ctio

ns,

th

en (

f�

g)(x

) �

(g�

f)(x

).fa

lse

f.If

fan

d g

are

poly

nom

ial

fun

ctio

ns,

th

en (

f�

g)(x

) �

(g�

f)(x

).tr

ue

2.L

et f

(x)

�2x

�5

and

g(x)

�x2

�1.

a.E

xpla

in i

n w

ords

how

you

wou

ld f

ind

(f�

g)(�

3). (

Do

not

act

ual

ly d

o an

y ca

lcu

lati

ons.

)S

amp

le a

nsw

er:

Sq

uar

e �

3 an

d a

dd

1.T

ake

the

nu

mb

er y

ou

get

,m

ult

iply

it b

y 2,

and

su

btr

act

5.

b.

Exp

lain

in

wor

ds h

ow y

ou w

ould

fin

d (g

�f)

(�3)

. (D

o n

ot a

ctu

ally

do

any

calc

ula

tion

s.)

Sam

ple

an

swer

:M

ult

iply

�3

by 2

an

d s

ub

trac

t 5.

Take

th

en

um

ber

yo

u g

et,s

qu

are

it,a

nd

ad

d 1

.

Rem

emb

er W

hat

Yo

u L

earn

ed

3.S

ome

stu

den

ts h

ave

trou

ble

rem

embe

rin

g th

e co

rrec

t or

der

in w

hic

h t

o ap

ply

the

two

orig

inal

fu

nct

ion

s w

hen

eva

luat

ing

a co

mpo

site

fu

nct

ion

. Wri

te t

hre

e se

nte

nce

s, e

ach

of

wh

ich

exp

lain

s h

ow t

o do

th

is i

n a

sli

ghtl

y di

ffer

ent

way

. (H

int:

Use

th

e w

ord

clos

est

inth

e fi

rst

sen

ten

ce, t

he

wor

ds i

nsi

de

and

outs

ide

in t

he

seco

nd,

an

d th

e w

ords

lef

tan

dri

ght

in t

he

thir

d.)

Sam

ple

an

swer

:1.

Th

e fu

nct

ion

th

at is

wri

tten

clo

sest

to

the

vari

able

is a

pp

lied

fir

st.2

.Wo

rk f

rom

th

e in

sid

e to

th

e o

uts

ide.

3.W

ork

fro

m r

igh

t to

left

.

f � g

f � g

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A1

Page 2: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A2 Glencoe Algebra 2

Answers (Lesson 7-1)

Exer

cise

s

Exam

ple

Cha

pter

76

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Stud

y Gu

ide

and

Inte

rven

tion

Op

erat

ion

s o

n F

un

ctio

ns

Ari

thm

etic

Op

erat

ion

s

Sum

(f�

g)(x

) �

f(x)

�g

(x)

Diff

eren

ce(f

�g)

(x)

�f(

x) �

g(x

)O

per

atio

ns

wit

h F

un

ctio

ns

Pro

duct

(f�

g)(x

) �

f(x)

�g

(x)

Quo

tient

��(x

) �

, g

(x)

�0

Fin

d (

f�

g)(x

), (

f�

g)(x

), (

f�

g)(x

), a

nd

��(x

) fo

r f(

x) �

x2�

3x�

4an

d g

(x)

�3x

�2.

(f�

g)(x

) �

f(x)

�g(

x)A

dditi

on o

f fu

nctio

ns

�(x

2�

3x�

4) �

(3x

�2)

f(x)

�x2

�3x

�4,

g(x

) �

3x�

2

�x2

�6x

�6

Sim

plify

.

(f�

g)(x

) �

f(x)

�g(

x)S

ubtr

actio

n of

fun

ctio

ns

�(x

2�

3x�

4) �

(3x

�2)

f(x)

�x2

�3x

�4,

g(x

) �

3x�

2

�x2

�2

Sim

plify

.

(f�

g)(x

)�

f(x)

�g(

x)M

ultip

licat

ion

of f

unct

ions

�(x

2�

3x�

4)(3

x�

2)f(

x) �

x2�

3x�

4, g

(x)

�3x

�2

�x2

(3x

�2)

�3x

(3x

�2)

�4(

3x�

2)D

istr

ibut

ive

Pro

pert

y

�3x

3�

2x2

�9x

2�

6x�

12x

�8

Dis

trib

utiv

e P

rope

rty

�3x

3�

7x2

�18

x�

8S

impl

ify.

��(x

)�

Div

isio

n of

fun

ctio

ns

�, x

��2 3�

f(x)

�x2

�3x

�4

and

g(x

) �

3x�

2

Fin

d (

f�

g)(x

), (

f�

g)(x

), (

f�

g)(x

), a

nd

��(x

) fo

r ea

ch f

(x)

and

g(x

).

1.f(

x) �

8x�

3; g

(x)

�4x

�5

2.f(

x) �

x2�

x�

6; g

(x)

�x

�2

12x

�2;

4x�

8;32

x2

�28

x�

15;

x2

�2x

�8;

x2

�4;

,x�

�x

3�

x2

�8x

�12

;x

�3,

x�

2

3.f(

x) �

3x2

�x

�5;

g(x

) �

2x�

34.

f(x)

�2x

�1;

g(x

) �

3x2

�11

x�

4

3x2

�x

�2;

3x2

�3x

�8;

3x2

�13

x�

5;�

3x2

�9x

�3;

6x3

�11

x2

�13

x�

15;

6x3

�19

x2

�19

x�

4;

,x�

,x�

,�4

5.f(

x) �

x2�

1; g

(x)

x2�

1 �

,x�

�1;

x2

�1

�,

x�

�1;

x�

1,x

��

1;x

3�

x2

�x

�1,

x�

�1

1� x

�1

1� x

�1

1� x

�1

1 � 32x

�1

��

(3x

�1)

(x�

4)3 � 2

3x2

�x

�5

��

2x�

3

5 � 48x

�3

� 4x�

5

f � g

x2�

3x�

4�

�3x

�2

f(x)

� g(x)

f � g

f � g

f(x)

� g(x

)f � g

Exam

ple

1

Exam

ple

2

Exer

cise

s

7-1

Lesson 7-1

Cha

pter

77

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Co

mp

osi

tio

n o

f Fu

nct

ion

s

Co

mp

osi

tio

n

Sup

pose

fan

d g

are

func

tions

suc

h th

at t

he r

ange

of

gis

a s

ubse

t of

the

dom

ain

of f

.o

f F

un

ctio

ns

The

n th

e co

mpo

site

fun

ctio

n f

�g

can

be d

escr

ibed

by

the

equa

tion

[f�

g](

x) �

f[g

(x)]

.

For

f�

{(1,

2),

(3,

3),

(2,

4),

(4,

1)}

an

d g

�{(

1, 3

), (

3, 4

), (

2, 2

), (

4, 1

)},

fin

d f

�g

and

g�

fif

th

ey e

xist

.f[

g(1)

] �

f(3)

�3

f[g(

2)]

�f(

2) �

4f[

g(3)

] �

f(4)

�1

f[g(

4)]

�f(

1) �

2f

�g

�{(

1, 3

), (

2, 4

), (

3, 1

), (

4, 2

)}g[

f(1)

] �

g(2)

�2

g[f(

2)]

�g(

4) �

1g[

f(3)

] �

g(3)

�4

g[f(

4)]

�g(

1) �

3g

�f

�{(

1, 2

), (

2, 1

), (

3, 4

), (

4, 3

)}

Fin

d [

g�

h](

x) a

nd

[h

�g]

(x)

for

g(x)

�3x

�4

and

h(x

) �

x2�

1.[g

�h

](x)

�g[

h(x

)][h

�g]

(x)

�h

[g(x

)]�

g(x2

�1)

�h

(3x

�4)

�3(

x2�

1) �

4�

(3x

�4)

2�

1�

3x2

�7

�9x

2�

24x

�16

�1

�9x

2�

24x

�15

For

eac

h s

et o

f or

der

ed p

airs

, fin

d f

�g

and

g�

fif

th

ey e

xist

.

1.f

�{(

�1,

2),

(5,

6),

(0,

9)}

,2.

f�

{(5,

�2)

, (9,

8),

(�

4, 3

), (

0, 4

)},

g�

{(6,

0),

(2,

�1)

, (9,

5)}

g�

{(3,

7),

(�

2, 6

), (

4, �

2), (

8, 1

0)}

f�

g�

{(2,

2),(

6,9)

,(9,

6)};

f�

gd

oes

no

t ex

ist;

g�

f�

{(�

1,�

1),(

0,5)

,(5,

0)}

g�

f�

{(�

4,7)

,(0,

�2)

,(5,

6),(

9,10

)}

Fin

d [

f�

g](x

) an

d [

g�

f](x

).

3.f(

x) �

2x�

7; g

(x)

��

5x�

14.

f(x)

�x2

�1;

g(x

) �

�4x

2

[f�

g](

x)

��

10x

�5,

[f�

g](

x)

�16

x4

�1,

[g�

f](x

) �

�10

x�

36[g

�f]

(x)

��

4x4

�8x

2�

4

5.f(

x) �

x2�

2x; g

(x)

�x

�9

6.f(

x) �

5x�

4; g

(x)

�3

�x

[f�

g](

x)

�x

2�

16x

�63

,[f

�g

](x

) �

19 �

5x,

[g�

f](x

) �

x2

�2x

�9

[g�

f](x

) �

�1

�5x

Stud

y Gu

ide

and

Inte

rven

tion

(con

tinue

d)

Op

erat

ion

s o

n F

un

ctio

ns

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A2

Page 3: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A3 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-1)

Cha

pter

78

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

7-1

Skill

s Pr

actic

eO

per

atio

ns

on

Fu

nct

ion

s

Fin

d (

f�

g)(x

), (

f�

g)(x

), (

f�

g)(x

), a

nd

��(x

) fo

r ea

ch f

(x)

and

g(x

).

1.f(

x) �

x�

52x

�1;

9;2.

f(x)

�3x

�1

5x�

2;x

�4;

6x2

�7x

�3;

g(x)

�x

�4

�x x� �

5 4�

,x�

4g(

x) �

2x�

3�3 2x x

� �1 3

�,x

��3 2�

3.f(

x) �

x2x

2�

x�

4;x2

�x

�4;

4.f(

x) �

3x2�3x

3 x�5

�,x

�0;

�3x3 x�

5�

,x�

0;

g(x)

�4

�x

4x2

�x3

;,x

�4

g(x)

��5 x�

15x,

x�

0;�3 5x3 �

,x�

0

For

eac

h s

et o

f or

der

ed p

airs

, fin

d f

�g

and

g�

fif

th

ey e

xist

.

5.f

�{(

0, 0

), (

4, �

2)}

6.f

�{(

0, �

3), (

1, 2

), (

2, 2

)}g

�{(

0, 4

), (

�2,

0),

(5,

0)}

g�

{(�

3, 1

), (

2, 0

)}{(

0,�

2),(

�2,

0),(

5,0)

};{(

�3,

2),(

2,�

3)};

{(0,

4),(

4,0)

}{(

0,1)

,(1,

0),(

2,0)

}

7.f

�{(

�4,

3),

(�

1, 1

), (

2, 2

)}8.

f�

{(6,

6),

(�

3, �

3), (

1, 3

)}g

�{(

1, �

4), (

2, �

1), (

3, �

1)}

g�

{(�

3, 6

), (

3, 6

), (

6, �

3)}

{(1,

3),(

2,1)

,(3,

1)};

{(�

3,6)

,(3,

6),(

6,�

3)};

{(�

4,�

1),(

�1,

�4)

,(2,

�1)

}{(

6,�

3),(

�3,

6),(

1,6)

}

Fin

d [

g�

h](

x) a

nd

[h

�g]

(x).

9.g(

x) �

2x2x

�4;

2x�

210

.g(x

) �

�3x

�12

x�

3;�

12x

�1

h(x

) �

x�

2h

(x)

�4x

�1

11.g

(x)

�x

�6

x;x

12.g

(x)

�x

�3

x2

�3;

x2

�6x

�9

h(x

) �

x�

6h

(x)

�x2

13.g

(x)

�5x

5x2

�5x

�5;

14.g

(x)

�x

�2

2x2

�1;

2x2

�8x

�5

h(x

) �

x2�

x�

125

x2

�5x

�1

h(x

) �

2x2

�3

If f

(x)

�3x

, g(x

) �

x�

4, a

nd

h(x

) �

x2�

1, f

ind

eac

h v

alu

e.

15.f

[g(1

)]15

16.g

[h(0

)]3

17.g

[f(�

1)]

1

18.h

[f(5

)]22

419

.g[h

(�3)

]12

20.h

[f(1

0)]

899

21.f

[h(8

)]18

922

.[f

�(h

�g)

](1)

7223

.[f

�(g

�h

)](�

2)21

x2

� 4 �

x

f � g

x2

�x

�20

;

7-1

Lesson 7-1

Cha

pter

79

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Fin

d (

f�

g)(x

), (

f�

g)(x

), (

f�

g)(x

), a

nd

�� gf � �(x)

for

eac

h f

(x)

and

g(x

).

1.f(

x) �

2x�

12.

f(x)

�8x

23.

f(x)

�x2

�7x

�12

g(x)

�x

�3

g(x)

�g(

x) �

x2�

9

3x�

2;x

�4;

�8x4 x

� 21

�,x

�0;

2x2

�7x

�3;

7x�

21;

2x2

�5x

�3;

�8x4 x2�

1�

,x�

0;x

4�

7x3

�3x

2�

63x

�10

8;

�2 xx ��31

�,x

�3

8,x

�0;

8x4 ,

x�

0�x x

� �4 3

�,x

��

3

For

eac

h s

et o

f or

der

ed p

airs

, fin

d f

�g

and

g�

fif

th

ey e

xist

.

4.f

�{(

�9,

�1)

, (�

1, 0

), (

3, 4

)}5.

f�

{(�

4, 3

), (

0, �

2), (

1, �

2)}

g�

{(0,

�9)

, (�

1, 3

), (

4, �

1)}

g�

{(�

2, 0

), (

3, 1

)}{(

0,�

1),(

�1,

4),(

4,0)

};{(

�2,

�2)

,(3,

�2)

};{(

�9,

3),(

�1,

�9)

,(3,

�1)

}{(

�4,

1),(

0,0)

,(1,

0)}

6.f

�{(

�4,

�5)

, (0,

3),

(1,

6)}

7.f

�{(

0, �

3), (

1, �

3), (

6, 8

)}g

�{(

6, 1

), (

�5,

0),

(3,

�4)

}g

�{(

8, 2

), (

�3,

0),

(�

3, 1

)}{(

6,6)

,(�

5,3)

,(3,

�5)

};d

oes

no

t ex

ist;

{(�

4,0)

,(0,

�4)

,(1,

1)}

{(0,

0),(

1,0)

,(6,

2)}

Fin

d [

g�

h](

x) a

nd

[h

�g]

(x).

8.g(

x) �

3x9.

g(x)

��

8x10

.g(x

) �

x�

6h

(x)

�x

�4

h(x

) �

2x�

3h

(x)

�3x

23x

2�

6;3x

�12

;3x

�4

�16

x�

24;

�16

x�

33x

2�

36x

�10

8

11.g

(x)

�x

�3

12.g

(x)

��

2x13

.g(x

) �

x�

2h

(x)

�2x

2h

(x)

�x2

�3x

�2

h(x

) �

3x2

�1

2x2

�3;

�2x

2�

6x�

4;3x

2�

1;2x

2�

12x

�18

4x2

�6x

�2

3x2

�12

x�

13

If f

(x)

�x2

, g(x

) �

5x, a

nd

h(x

) �

x�

4, f

ind

eac

h v

alu

e.

14.f

[g(1

)]25

15.g

[h(�

2)]

1016

.h[f

(4)]

20

17.f

[h(�

9)]

2518

.h[g

(�3)

]�

1119

.g[f

(8)]

320

20.h

[f(2

0)]

404

21.[

f�

(h�

g)](

�1)

122

.[f

�(g

�h

)](4

)16

00

23.B

USI

NES

ST

he

fun

ctio

n f

(x)

�10

00 �

0.01

x2m

odel

s th

e m

anu

fact

uri

ng

cost

per

ite

mw

hen

xit

ems

are

prod

uce

d, a

nd

g(x)

�15

0 �

0.00

1x2

mod

els

the

serv

ice

cost

per

ite

m.

Wri

te a

fu

nct

ion

C(x

) fo

r th

e to

tal

man

ufa

ctu

rin

g an

d se

rvic

e co

st p

er i

tem

.C

(x)

�11

50 �

0.01

1x2

24.M

EASU

REM

ENT

Th

e fo

rmu

la f

�� 1n 2�

con

vert

s in

ches

nto

fee

t f,

an

d m

�� 52

f 80�co

nve

rts

feet

to

mil

es m

. Wri

te a

com

posi

tion

of

fun

ctio

ns

that

con

vert

s in

ches

to

mil

es.

[m�

f]n

�� 63

,n 360

1 � x2

Prac

tice

Op

erat

ion

s o

n F

un

ctio

ns

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A3

Page 4: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A4 Glencoe Algebra 2

Answers (Lesson 7-1)

1.A

REA

Ber

nar

d w

ants

to

know

th

e ar

ea o

f a

figu

re m

ade

by jo

inin

g an

equ

ilat

eral

tri

angl

e an

d sq

uar

e al

ong

an

edge

. Th

e fu

nct

ion

f(s

) �

�� 43 � �s2

give

s th

ear

ea o

f an

equ

ilat

eral

tr

ian

gle

wit

h s

ide

s.T

he

fun

ctio

n g

(s)

�s2

give

s th

e ar

ea o

f a

squ

are

wit

h s

ide

s.W

hat

fu

nct

ion

h(s

)gi

ves

the

area

of

the

figu

re a

s a

fun

ctio

n o

fit

s si

de l

engt

h s

?

h(s

) �

(f�

g)(

s) �

(�� 43 � ��

1)s2

2.PR

ICIN

GA

com

pute

r co

mpa

ny

deci

des

to c

onti

nu

ousl

y ad

just

th

e pr

icin

g of

an

ddi

scou

nts

to

its

prod

uct

s in

an

eff

ort

tore

mai

n c

ompe

titi

ve. T

he

fun

ctio

n P

(t)

give

s th

e sa

le p

rice

of

its

Su

per2

000

com

pute

r as

a f

un

ctio

n o

f ti

me.

Th

efu

nct

ion

D(t

) gi

ves

the

valu

e of

a s

peci

aldi

scou

nt

it o

ffer

s to

val

ued

cu

stom

ers.

How

mu

ch w

ould

val

ued

cu

stom

ers

hav

eto

pay

for

on

e S

upe

r200

0 co

mpu

ter?

(P�

D)(

t)

3.LA

VA

Afr

esh

ly e

ject

ed l

ava

rock

imm

edia

tely

beg

ins

to c

ool

dow

n. T

he

tem

pera

ture

of

the

lava

roc

k in

deg

rees

Fah

ren

hei

t as

a f

un

ctio

n o

f ti

me

is g

iven

by T

(t).

Let

C(F

) be

th

e fu

nct

ion

th

atgi

ves

degr

ees

Cel

siu

s as

a f

un

ctio

n o

fde

gree

s F

ahre

nh

eit.

Wh

at f

un

ctio

n g

ives

the

tem

pera

ture

of

the

lava

roc

k in

degr

ees

Cel

siu

s as

a f

un

ctio

n o

f ti

me?

C

(T(t

))

4.EN

GIN

EER

ING

Agr

oup

of e

ngi

nee

rs i

sde

sign

ing

a st

aple

gu

n. O

ne

team

dete

rmin

es t

hat

th

e sp

eed

of i

mpa

ct s

ofth

e st

aple

(in

fee

t pe

r se

con

d) a

s a

fun

ctio

n o

f th

e h

andl

e le

ngt

h �

(in

inch

es)

is g

iven

by

s(�)

�40

�3�

. Ase

con

d te

am d

eter

min

es t

hat

th

en

um

ber

of s

hee

ts N

that

can

be

stap

led

as a

fu

nct

ion

of

the

impa

ct s

peed

is

give

n b

y N

(s)

��s

� 310 �

. Wh

at f

un

ctio

n

give

s N

as a

fu

nct

ion

of

�?N

(s(�

)) �

10 �

HO

T A

IR B

ALL

OO

NS

For

Exe

rcis

es 5

and

6, u

se t

he

foll

owin

g in

form

atio

n.

Han

nah

an

d Te

rry

wen

t on

a o

ne-

hou

r h

otai

r ba

lloo

n r

ide.

Let

T(A

) be

th

e ou

tsid

e ai

rte

mpe

ratu

re a

s a

fun

ctio

n o

f al

titu

de a

nd

let

A(t

) be

th

e al

titu

de o

f th

e ba

lloo

n a

s a

fun

ctio

n o

f ti

me.

5.W

hat

fu

nct

ion

des

crib

es t

he

air

tem

pera

ture

Han

nah

an

d Te

rry

felt

at

diff

eren

t ti

mes

du

rin

g th

eir

trip

?T

(A(t

))

6.S

ketc

h a

gra

ph o

f th

e fu

nct

ion

you

wro

tefo

r E

xerc

ise

5 ba

sed

on t

he

grap

hs

for

T(A

) an

d A

(t)

that

are

giv

en.

Teperature (ºF) 10 02030405060

Tim

e (m

inu

tes)

1020

3040

5060

Teperature (ºF) 10 02030405060

Alt

itu

de

(km

)1

23

45

6

Altitude (km) 1 023456

Tim

e (m

inu

tes)

1020

3040

5060

s

Cha

pter

710

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Wor

d Pr

oble

m P

ract

ice

Op

erat

ion

s o

n F

un

ctio

ns

Lesson 7-1

Cha

pter

711

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Rel

ativ

e M

axim

um

Val

ues

Th

e gr

aph

of

f(x)

�x3

�6x

�9

show

s a

rela

tive

max

imu

m v

alu

e so

mew

her

e be

twee

n f

(�2)

an

d f(

�1)

. You

can

obt

ain

a

clos

er a

ppro

xim

atio

n b

y co

mpa

rin

g va

lues

su

ch a

s th

ose

show

n i

n t

he

tabl

e.

To t

he

nea

rest

ten

th a

rel

ativ

e m

axim

um

va

lue

for

f(x)

is

�3.

3.

Usi

ng

a ca

lcu

lato

r to

fin

d p

oin

ts, g

rap

h e

ach

fu

nct

ion

. To

the

nea

rest

te

nth

, fin

d a

rel

ativ

e m

axim

um

val

ue

of t

he

fun

ctio

n.

1.f(

x) �

x(x2

�3)

rel.

max

.of

2.0

2.f(

x) �

x3�

3x�

3re

l.m

ax.o

f �

1.0

3.f(

x) �

x3�

9x�

2re

l.m

ax.o

f 8.

44.

f(x)

�x3

�2x

2�

12x

�24

rel.

max

.of

3.3

5

x

f(x)

O1

2

x

f(x)

O2

x

f(x)

O

x

f(x)

O

xf(

x)

�2

�5

�1.

5�

3.37

5

�1.

4�

3.34

4

�1.

3�

3.39

7

�1

�4

x

f(x)

O2

–2–4 –8 –12

–16

–20

–44

f(x)

� x

3 �

6x

� 9

Enri

chm

ent

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A4

Page 5: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A5 Glencoe Algebra 2

An

swer

s

Answers (Lessons 7-1 and 7-2)

Cha

pter

712

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-1

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Spre

adsh

eet

Act

ivit

yO

per

atio

ns

on

Fu

nct

ion

s

Stu

dy

and

use

th

e sp

read

shee

t ab

ove.

1.F

ind

k(x)

�(3

x�

2) �

(x2

�2x

). H

ow d

oes

it c

ompa

re t

o h

(x)?

k(x)

�x

2�

x�

2 �

h(x

)

2.C

hang

e th

e fu

ncti

ons

in t

he s

prea

dshe

et t

o f(

x) �

� 2x �, g

(x)

�1

�x2

, and

h(x)

�1

�� 2x �

�x2

. How

are

th

ese

fun

ctio

ns

rela

ted?

Is

it t

rue

that

f(x)

�g(

x) �

h(x

)?(f

�g

)(x)

�h

(x);

yes

3.M

ake

a co

nje

ctu

re a

bou

t (f

�g)

(x)

for

any

fun

ctio

ns

f(x)

an

d g(

x).

(f�

g)(

x) �

f(x)

�g

(x)

4.M

ake

a co

nje

ctu

re a

bou

t (f

�g)

(x)

for

any

fun

ctio

ns

f(x)

an

d g(

x). U

se t

he

spre

adsh

eet

to t

est

you

r co

nje

ctu

re. D

oes

it a

ppea

r to

be

tru

e? E

xpla

inyo

ur

answ

er.

(f�

g)(

x) �

f(x)

�g

(x);

See

stu

den

ts’w

ork

.

Fin

d (

f�

g)(x

), (

f�

g)(x

), f

or e

ach

f(x

) an

d g

(x).

Use

th

e sp

read

shee

t to

fi

nd

fu

nct

ion

val

ues

to

veri

fy y

our

solu

tion

s. 5-

7.S

ee s

tud

ents

’sp

read

shee

ts.

5.f(

x) �

6x�

86.

f(x)

�x2

�1

7.f(

x) �

10x2

g(x)

�9

�x

g(x)

�3x

�4

g(x)

�6

�x2

7x�

17;

5x�

1x

2�

3x�

3;x

2�

3x�

59x

2�

6;11

x2

�6

It i

s po

ssib

le t

o pe

rfor

m o

pera

tion

s on

fu

nct

ion

s su

ch a

s ad

diti

on,

subt

ract

ion

, mu

ltip

lica

tion

an

d di

visi

on. Y

ou c

an u

se a

spr

eads

hee

t to

in

vest

igat

e th

e re

lati

onsh

ips

amon

g fu

nct

ion

s.

Con

sid

er t

he

fun

ctio

ns

f(x)

�3x

�2,

g(x

) �

x2�

2x, a

nd

h(x

) �

x2�

x+

2.F

ind

th

e fu

nct

ion

val

ues

of

each

fu

nct

ion

for

sev

eral

val

ues

of

x.D

oes

it a

pp

ear

that

f(x

) �

g(x)

�h

(x)?

Use

Col

um

n A

for

the

chos

en v

alu

es o

f x.

Col

um

ns

B, C

, an

d E

are

f(x

), g

(x),

an

d h

(x)

resp

ecti

vely

. Use

Col

um

n D

for

f(x

)�g(

x).

For

eve

ry v

alu

e of

x, f

(x)�

g(x)

�h

(x).

A1 9Fu

nct

ion

s.xl

s

x2 3 4 5 6 7 8

0–1–2

.5–4 1 4 12

Bf(

x)

2–1–5

.5–1

0 5 14 38

Cg(

x)

0311

.2524 –1 8

120

Eh(

x)

225.

7514 4 22 158

Df(

x) +

g(x

) 225.

7514 4 22 158

Sh

eet

1S

hee

t 2

Sh

eet

3

Exer

cise

s

Lesson 7-2

Cha

pter

713

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-2

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Less

on R

eadi

ng G

uide

Inve

rse

Fu

nct

ion

s an

d R

elat

ion

sG

et R

ead

y fo

r th

e Le

sso

nR

ead

th

e in

trod

uct

ion

to

Les

son

7-2

in

you

r te

xtb

ook

.

Afu

ncti

on m

ulti

plie

s a

num

ber

by 3

and

the

n ad

ds 5

to

the

resu

lt.

Wha

t do

es t

he

inve

rse

fun

ctio

n d

o, a

nd

in w

hat

ord

er?

Sam

ple

an

swer

:It

fir

st s

ub

trac

ts 5

fro

m t

he

nu

mb

er a

nd

th

en d

ivid

es t

he

resu

lt b

y 3.

Rea

d t

he

Less

on

1.C

ompl

ete

each

sta

tem

ent.

a.If

tw

o re

lati

ons

are

inve

rses

, th

e do

mai

n o

f on

e re

lati

on i

s th

e of

the

oth

er.

b.

Su

ppos

e th

at g

is a

rel

atio

n a

nd

that

th

e po

int

(4, �

2) i

s on

its

gra

ph. T

hen

a p

oin

t

on t

he

grap

h o

f g�

1is

.

c.T

he

test

can

be

use

d on

th

e gr

aph

of

a fu

nct

ion

to

dete

rmin

e

wh

eth

er t

he

fun

ctio

n h

as a

n i

nve

rse

fun

ctio

n.

d.

If y

ou a

re g

iven

th

e gr

aph

of

a fu

nct

ion

, you

can

fin

d th

e gr

aph

of

its

inve

rse

by

refl

ecti

ng

the

orig

inal

gra

ph o

ver

the

lin

e w

ith

equ

atio

n

.

e.If

fan

d g

are

inve

rse

fun

ctio

ns,

th

en (

f�

g)(x

) �

an

d

(g�

f)(x

) �

.

f.A

fun

ctio

n h

as a

n i

nve

rse

that

is

also

a f

un

ctio

n o

nly

if

the

give

n f

un

ctio

n i

s

.

g.S

upp

ose

that

h(x

) is

a f

un

ctio

n w

hos

e in

vers

e is

als

o a

fun

ctio

n. I

f h

(5)

�12

, th

enh

�1 (

12)

�.

2.A

ssu

me

that

f(x

) is

a o

ne-

to-o

ne

fun

ctio

n d

efin

ed b

y an

alg

ebra

ic e

quat

ion

. Wri

te t

he

fou

r st

eps

you

wou

ld f

ollo

w i

n o

rder

to

fin

d th

e eq

uat

ion

for

f�

1 (x)

.

1.R

epla

ce f

(x)

wit

h y

in t

he

ori

gin

al e

qu

atio

n.

2.In

terc

han

ge

xan

d y

.

3.S

olv

e fo

r y.

4.R

epla

ce y

wit

h f

�1 (

x).

Rem

emb

er W

hat

Yo

u L

earn

ed

3.A

good

way

to

rem

embe

r so

met

hin

g n

ew i

s to

rel

ate

it t

o so

met

hin

g yo

u a

lrea

dy k

now

.H

ow a

re t

he v

erti

cal

and

hori

zont

al l

ine

test

s re

late

d?S

amp

le a

nsw

er:T

he

vert

ical

line

test

det

erm

ines

wh

eth

er a

rel

atio

n is

a f

un

ctio

n b

ecau

se t

he

ord

ered

pai

rs in

a f

un

ctio

n c

an h

ave

no

rep

eate

d x

-val

ues

.Th

e h

ori

zon

tal l

ine

test

det

erm

ines

wh

eth

er a

fu

nct

ion

is o

ne-

to-o

ne

bec

ause

a o

ne-

to-o

ne

fun

ctio

n c

ann

ot

hav

e an

y re

pea

ted

y-v

alu

es.

5

on

e-to

-on

e

xx

y �

x

ho

rizo

nta

l lin

e

(�2,

4)

ran

ge

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A5

Page 6: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A6 Glencoe Algebra 2

Answers (Lesson 7-2)

Exam

ple

Exer

cise

s

Cha

pter

714

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-2

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Stud

y Gu

ide

and

Inte

rven

tion

Inve

rse

Fu

nct

ion

s an

d R

elat

ion

sFi

nd

Inve

rses

Inve

rse

Rel

atio

ns

Two

rela

tions

are

inve

rse

rela

tions

if a

nd o

nly

if w

hene

ver

one

rela

tion

cont

ains

the

el

emen

t (a

, b

), t

he o

ther

rel

atio

n co

ntai

ns t

he e

lem

ent

(b,

a).

Pro

per

ty o

f In

vers

e S

uppo

se f

and

f�1

are

inve

rse

func

tions

.F

un

ctio

ns

The

n f(

a) �

bif

and

only

if f

�1 (

b) �

a.

Fin

d t

he

inve

rse

of t

he

fun

ctio

n f

(x)

�x

�. T

hen

gra

ph

th

efu

nct

ion

an

d i

ts i

nve

rse.

Ste

p 1

Rep

lace

f(x

) w

ith

yin

th

e or

igin

al e

quat

ion

.

f(x)

��2 5� x

�→

y�

�2 5� x�

Ste

p 2

Inte

rch

ange

xan

d y.

x�

�2 5� y�

Ste

p 3

Sol

ve f

or y

.

x�

�2 5� y�

Inve

rse

5x�

2y�

1M

ultip

ly e

ach

side

by

5.

5x�

1 �

2yA

dd 1

to

each

sid

e.

(5x

�1)

�y

Div

ide

each

sid

e by

2.

Th

e in

vers

e of

f(x

) �

�2 5� x�

is f

�1 (

x) �

(5x

�1)

.

Fin

d t

he

inve

rse

of e

ach

fu

nct

ion

. Th

en g

rap

h t

he

fun

ctio

n a

nd

its

in

vers

e.

1.f(

x) �

x�

12.

f(x)

�2x

�3

3.f(

x) �

x�

2

f�1 (

x)

�x

�f�

1 (x

) �

x�

f�1 (

x)

�4x

�8

f–1(x

) � 4

x �

8

f(x)

� 1 – 4x

� 2 x

f(x)

O

f(x)

� 2

x �

3

f–1(x

) � 1 – 2x

� 3 – 2

x

f(x)

O

f(x)

� 2 – 3x

� 1

f–1(x

) � 3 – 2x

� 3 – 2

x

f(x)

O

3 � 21 � 2

3 � 23 � 2

1 � 42 � 3

1 � 21 � 5

1 � 2

1 � 51 � 5

1 � 51 � 5

x

f(x)

O

f(x)

� 2 – 5x

� 1 – 5

f–1(x

) � 5 – 2x

� 1 – 2

1 � 52 � 5

Exam

ple

1

Exam

ple

2

7-2

Lesson 7-2

Cha

pter

715

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-2

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Inve

rses

of

Rel

atio

ns

and

Fu

nct

ion

s

Inve

rse

Fu

nct

ion

sTw

o fu

nctio

ns f

and

gar

e in

vers

e fu

nctio

ns if

and

onl

y if

[f�

g](

x) �

xan

d [g

�f]

(x)

�x.

Det

erm

ine

wh

eth

er f

(x)

�2x

�7

and

g(x

) �

(x�

7) a

re

inve

rse

fun

ctio

ns.

[f�

g](x

) �

f[g(

x)]

[g�

f](x

) �

g[f(

x)]

�f ��1 2� (

x�

7)�

�g(

2x�

7)

�2 ��1 2� (

x�

7)��

7�

�1 2� (2x

�7

�7)

�x

�7

�7

�x

�x

Th

e fu

nct

ion

s ar

e in

vers

es s

ince

bot

h [

f�

g](x

) �

xan

d [g

�f]

(x)

�x.

Det

erm

ine

wh

eth

er f

(x)

�4x

�an

d g

(x)

�x

�3

are

inve

rse

fun

ctio

ns.

[f�

g](x

) �

f[g(

x)]

�f ��1 4� x

�3 �

�4 ��1 4� x

�3 �

��1 3�

�x

�12

��1 3�

�x

�11

�2 3�

Sin

ce [

f�

g](x

) �

x, t

he

fun

ctio

ns

are

not

in

vers

es.

Det

erm

ine

wh

eth

er e

ach

pai

r of

fu

nct

ion

s ar

e in

vers

e fu

nct

ion

s.

1.f(

x) �

3x�

12.

f(x)

��1 4� x

�5

3.f(

x) �

�1 2� x�

10

g(x)

��1 3� x

��1 3�

yes

g(x)

�4x

�20

yes

g(x)

�2x

�� 11 0�

no

4.f(

x) �

2x�

55.

f(x)

�8x

�12

6.f(

x) �

�2x

�3

g(x)

�5x

�2

no

g(x)

��1 8� x

�12

no

g(x)

��

�1 2� x�

�3 2�ye

s

7.f(

x) �

4x�

�1 2�8.

f(x)

�2x

��3 5�

9.f(

x) �

4x�

�1 2�

g(x)

��1 4� x

��1 8�

yes

g(x)

�� 11 0�

(5x

�3)

yes

g(x)

��1 2� x

��3 2�

no

10.f

(x)

�10

�� 2x �

11.f

(x)

�4x

��4 5�

12.f

(x)

�9

��3 2� x

g(x)

�20

�2x

yes

g(x)

�� 4x �

��1 5�

yes

g(x)

��2 3� x

�6

yes

1 � 41 � 3

1 � 2

Stud

y Gu

ide

and

Inte

rven

tion

(con

tinue

d)

Inve

rse

Fu

nct

ion

s an

d R

elat

ion

s

Exer

cise

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A6

Page 7: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A7 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-2)

Cha

pter

716

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-2

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Skill

s Pr

actic

eIn

vers

e F

un

ctio

ns

and

Rel

atio

ns

Fin

d t

he

inve

rse

of e

ach

rel

atio

n.

1.{(

3, 1

), (

4, �

3), (

8, �

3)}

2.{(

�7,

1),

(0,

5),

(5,

�1)

}{(

1,3)

,(�

3,4)

,(�

3,8)

}{(

1,�

7),(

5,0)

,(�

1,5)

}

3.{(

�10

, �2)

, (�

7, 6

), (

�4,

�2)

, (�

4, 0

)}4.

{(0,

�9)

, (5,

�3)

, (6,

6),

(8,

�3)

}{(

�2,

�10

),(6

,�7)

,(�

2,�

4),(

0,�

4)}

{(�

9,0)

,(�

3,5)

,(6,

6),(

�3,

8)}

5.{(

�4,

12)

, (0,

7),

(9,

�1)

, (10

, �5)

}6.

{(�

4, 1

), (

�4,

3),

(0,

�8)

, (8,

�9)

}{(

12,�

4),(

7,0)

,(�

1,9)

,(�

5,10

)}{(

1,�

4),(

3,�

4),(

�8,

0),(

�9,

8)}

Fin

d t

he

inve

rse

of e

ach

fu

nct

ion

. Th

en g

rap

h t

he

fun

ctio

n a

nd

its

in

vers

e.

7.y

�4

8.f(

x) �

3x9.

f(x)

�x

�2

x�

4f�

1 (x

) �

�1 3� xf�

1 (x

) �

x�

2

10.g

(x)

�2x

�1

11.h

(x)

��1 4� x

12.y

��2 3� x

�2

g�

1 (x

) �

�x� 2

1�

h�

1 (x

) �

4xy

��3 2� x

�3

Det

erm

ine

wh

eth

er e

ach

pai

r of

fu

nct

ion

s ar

e in

vers

e fu

nct

ion

s.

13.f

(x)

�x

�1

no

14.f

(x)

�2x

�3

yes

15.f

(x)

�5x

�5

yes

g(x)

�1

�x

g(x)

��1 2� (

x�

3)g(

x) �

�1 5� x�

1

16.f

(x)

�2x

yes

17.h

(x)

�6x

�2

no

18.f

(x)

�8x

�10

yes

g(x)

��1 2� x

g(x)

��1 6� x

�3

g(x)

��1 8� x

��5 4�

x

y

Ox

h(x)

Ox

g(x)

O

x

f(x)

Ox

f(x)

Ox

y

O

7-2

Lesson 7-2

Cha

pter

717

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-2

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Fin

d t

he

inve

rse

of e

ach

rel

atio

n.

1.{(

0, 3

), (

4, 2

), (

5, �

6)}

2.{(

�5,

1),

(�

5, �

1), (

�5,

8)}

{(3,

0),(

2,4)

,(�

6,5)

}{(

1,�

5),(

�1,

�5)

,(8,

�5)

}

3.{(

�3,

�7)

, (0,

�1)

, (5,

9),

(7,

13)

}4.

{(8,

�2)

, (10

, 5),

(12

, 6),

(14

, 7)}

{(�

7,�

3),(

�1,

0),(

9,5)

,(13

,7)}

{(�

2,8)

,(5,

10),

(6,1

2),(

7,14

)}

5.{(

�5,

�4)

, (1,

2),

(3,

4),

(7,

8)}

6.{(

�3,

9),

(�

2, 4

), (

0, 0

), (

1, 1

)}{(

�4,

�5)

,(2,

1),(

4,3)

,(8,

7)}

{(9,

�3)

,(4,

�2)

,(0,

0),(

1,1)

}

Fin

d t

he

inve

rse

of e

ach

fu

nct

ion

. Th

en g

rap

h t

he

fun

ctio

n a

nd

its

in

vers

e.

7.f(

x) �

�3 4� x8.

g(x)

�3

�x

9.y

�3x

�2

f�1 (

x)

��4 3� x

g�

1 (x

) �

x�

3y

��x

� 32

Det

erm

ine

wh

eth

er e

ach

pai

r of

fu

nct

ion

s ar

e in

vers

e fu

nct

ion

s.

10.f

(x)

�x

�6

yes

11.f

(x)

��

4x�

1ye

s12

.g(x

) �

13x

�13

no

g(x)

�x

�6

g(x)

��1 4� (

1 �

x)h

(x)

�� 11 3�

x�

1

13.f

(x)

�2x

no

14.f

(x)

��6 7� x

yes

15.g

(x)

�2x

�8

yes

g(x)

��

2xg(

x) �

�7 6� xh

(x)

��1 2� x

�4

16. M

EASU

REM

ENT

Th

e po

ints

(63

, 121

), (

71, 1

80),

(67

, 140

), (

65, 1

08),

an

d (7

2, 1

65)

give

the

wei

ght

in p

oun

ds a

s a

fun

ctio

n o

f h

eigh

t in

in

ches

for

5 s

tude

nts

in

a c

lass

. Giv

e th

epo

ints

for

th

ese

stu

den

ts t

hat

rep

rese

nt

hei

ght

as a

fu

nct

ion

of

wei

ght.

(121

,63)

,(18

0,71

),(1

40,6

7),(

108,

65),

(165

,72)

REM

OD

ELIN

GF

or E

xerc

ises

17

and

18,

use

th

e fo

llow

ing

info

rmat

ion

.T

he

Cle

arys

are

rep

laci

ng

the

floo

rin

g in

th

eir

15 f

oot

by 1

8 fo

ot k

itch

en. T

he

new

flo

orin

gco

sts

$17.

99 p

er s

quar

e ya

rd. T

he

form

ula

f(x

) �

9xco

nve

rts

squ

are

yard

s to

squ

are

feet

.

17.F

ind

the

inve

rse

f�1 (

x). W

hat

is

the

sign

ific

ance

of

f�1 (

x) f

or t

he

Cle

arys

?f�

1 (x

) �

�x 9� ;It

will

allo

w t

hem

to

co

nver

t th

e sq

uar

e fo

ota

ge

of

thei

r ki

tch

en f

loo

r to

squ

are

yard

s,so

th

ey c

an t

hen

cal

cula

te t

he

cost

of

the

new

flo

ori

ng

.

18.W

hat

wil

l th

e n

ew f

loor

ing

cost

th

e C

lear

y’s?

$539

.70

x

y

Ox

g(x)

Ox

f(x)

OPrac

tice

Inve

rse

Fu

nct

ion

s an

d R

elat

ion

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A7

Page 8: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A8 Glencoe Algebra 2

Answers (Lesson 7-2)

1.V

OLU

ME

Jaso

n w

ants

to

mak

e a

sph

eric

al w

ater

coo

ler

that

can

hol

d h

alf

a cu

bic

met

er o

f w

ater

. He

know

s th

at

V�

r3, b

ut

he

nee

ds t

o kn

ow h

ow t

o

fin

d r

give

n V

. Fin

d th

is i

nve

rse

fun

ctio

n.

r�

�3�

2.EX

ERC

ISE

Ale

x be

gan

a n

ew e

xerc

ise

rou

tin

e. T

o ga

in t

he

max

imu

m b

enef

itfr

om h

is e

xerc

ise,

Ale

x ca

lcu

late

d h

ism

axim

um

tar

get

hea

rt r

ate

usi

ng

the

fun

ctio

n. f

(x)

�0.

85(2

20 �

x) w

her

e x

repr

esen

ts h

is a

ge. F

ind

the

inve

rse

ofth

is f

un

ctio

n.

f�1 (

x) �

220

3.R

OC

KET

ST

he

alti

tude

of

a ro

cket

in

feet

as

a fu

nct

ion

of

tim

e is

giv

en b

yf(

t) =

49t

2 , w

her

e t

≥0.

Fin

d th

e in

vers

eof

th

is f

un

ctio

n a

nd

dete

rmin

e th

e ti

mes

wh

en t

he

rock

et w

ill

be 1

0, 1

00, a

nd

1000

fee

t h

igh

. Rou

nd

you

r an

swer

s to

the

nea

rest

hu

ndr

edth

of

a se

con

d.

f�1 (

t) �

; 10

ft a

t 0.

45 s

,

100

ft a

t 1.

43 s

, 100

0 ft

at

4.52

s

4.SE

LF-I

NV

ERTI

BLE

Kar

en f

inds

th

ein

com

plet

e gr

aph

of

a fu

nct

ion

in

th

eba

ck o

f h

er e

ngi

nee

rin

g h

andb

ook.

Th

efu

nct

ion

is

grap

hed

in

th

e fi

gure

bel

ow.

Kar

en k

now

s th

at t

his

fu

nct

ion

is

its

own

in

vers

e. A

rmed

wit

h t

his

know

ledg

e, e

xten

d th

e gr

aph

for

va

lues

of

xbe

twee

n �

7 an

d 2.

PLA

NET

SF

or E

xerc

ises

5 a

nd

6, u

seth

e fo

llow

ing

info

rmat

ion

.

Th

e ap

prox

imat

e di

stan

ce o

f a

plan

et f

rom

th

e S

un

is

give

n b

y d

�T

�2 3�w

her

e d

is

dist

ance

in

ast

ron

omic

al u

nit

s an

d T

isE

arth

yea

rs. A

n a

stro

nom

ical

un

it i

s th

edi

stan

ce o

f th

e E

arth

fro

m t

he

Su

n.

5.S

olve

for

Tin

ter

ms

of d

.T

�d

1.5

6.P

luto

is

abou

t 39

.44

tim

es a

s fa

r fr

omth

e S

un

as

the

Ear

th. A

bou

t h

ow m

any

year

s do

es i

t ta

ke P

luto

to

orbi

t th

eS

un

? 24

8 yr

y

xO

5

5

-5

-5

�t �

�7

x� 0.

85

3V � 4�

4 � 3

Cha

pter

718

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-2

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Wor

d Pr

oble

m P

ract

ice

Inve

rse

Fu

nct

ion

s an

d R

elat

ion

s

Lesson 7-2

Cha

pter

719

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-2

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Enri

chm

ent

Rea

din

g A

lgeb

raIn

mat

hem

atic

s, t

he

term

gro

up

has

a s

peci

al m

ean

ing.

Th

e fo

llow

ing

nu

mbe

red

sen

ten

ces

disc

uss

th

e id

ea o

f gr

oup

and

one

inte

rest

ing

exam

ple

of a

gro

up.

01To

be

a gr

oup,

a s

et o

f el

emen

ts a

nd

a bi

nar

y op

erat

ion

mu

st s

atis

fy f

our

con

diti

ons:

th

e se

t m

ust

be

clos

ed u

nde

r th

e op

erat

ion

, th

e op

erat

ion

mu

st b

e as

soci

ativ

e, t

her

e m

ust

be

an i

den

tity

ele

men

t, a

nd

ever

yel

emen

t m

ust

hav

e an

in

vers

e.

02T

he

foll

owin

g si

x fu

nct

ion

s fo

rm a

gro

up

un

der

the

oper

atio

n o

f

com

posi

tion

of

fun

ctio

ns:

f1(

x) �

x,f 2

(x)

��1 x� ,

f3(

x) �

1 �

x,

f 4(x

) �

�(x� x

1)�

, f5(

x) �

� (x�x

1)�

, an

d f 6

(x)

�� (1

�1x)

�.

03T

his

gro

up

is a

n e

xam

ple

of a

non

com

mu

tati

ve g

rou

p. F

or e

xam

ple,

f 3�

f 2�

f 4, b

ut

f 2�

f 3�

f 6.

04S

ome

expe

rim

enta

tion

wit

h t

his

gro

up

wil

l sh

ow t

hat

th

e id

enti

tyel

emen

t is

f1.

05E

very

ele

men

t is

its

ow

n i

nve

rse

exce

pt f

or f

4an

d f 6

, eac

h o

f w

hic

h i

s th

ein

vers

e of

th

e ot

her

.

Use

th

e p

arag

rap

h t

o an

swer

th

ese

qu

esti

ons.

1.E

xpla

in w

hat

it

mea

ns

to s

ay t

hat

a s

et i

s cl

osed

un

der

an o

pera

tion

. Is

the

set

of p

osit

ive

inte

gers

clo

sed

un

der

subt

ract

ion

?P

erfo

rmin

g t

he

op

er-

atio

n o

n a

ny t

wo

ele

men

ts o

f th

e se

t re

sult

s in

an

ele

men

t o

f th

esa

me

set.

No

,3 a

nd

4 a

re p

osi

tive

inte

ger

s bu

t 3

� 4

is n

ot.

2.S

ubt

ract

ion

is

a n

onco

mm

uta

tive

ope

rati

on f

or t

he

set

of i

nte

gers

. Wri

tean

in

form

al d

efin

itio

n o

f n

onco

mm

uta

tive

.T

he

ord

er in

wh

ich

th

eel

emen

ts a

re u

sed

wit

h t

he

op

erat

ion

can

aff

ect

the

resu

lt.

3.F

or t

he

set

of i

nte

gers

, wh

at i

s th

e id

enti

ty e

lem

ent

for

the

oper

atio

n o

fm

ult

ipli

cati

on?

Just

ify

you

r an

swer

. 1,

bec

ause

,fo

r ev

ery

inte

ger

a,a

�1

�a

and

1 �

a�

a.

4.E

xpla

in h

ow t

he

foll

owin

g st

atem

ent

rela

tes

to s

ente

nce

05:

(f6

�f 4

)(x)

�f 6

[f4(

x)]

�f 6�� (1

�1x)

���

�x

�f 1

(x).

It s

ho

ws

that

f4

is t

he

inve

rse

of

f 6.1

��

�1�

(x x�

1)�

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A8

Page 9: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A9 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-3)

Cha

pter

720

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-3

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Less

on R

eadi

ng G

uide

Sq

uar

e R

oo

t F

un

ctio

ns

Get

Rea

dy

for

the

Less

on

Rea

d t

he

intr

odu

ctio

n t

o L

esso

n 7

-3 i

n y

our

text

boo

k.

If t

he

wei

ght

to b

e su

ppor

ted

by a

ste

el c

able

is

dou

bled

, sh

ould

th

e di

amet

er o

f th

e su

ppor

tca

ble

also

be

dou

bled

? If

not

, by

wh

at n

um

ber

shou

ld t

he

diam

eter

be

mu

ltip

lied

?

no

;�

2�

Rea

d t

he

Less

on

1.M

atch

eac

h s

quar

e ro

ot f

un

ctio

n f

rom

th

e li

st o

n t

he

left

wit

h i

ts d

omai

n a

nd

ran

ge f

rom

the

list

on

th

e ri

ght.

a.y

��

x�iv

i.do

mai

n: x

�0;

ran

ge: y

�3

b.

y�

�x

�3

�vi

iiii

.do

mai

n: x

�0;

ran

ge: y

�0

c.y

��

x��

3i

iii.

dom

ain

: x�

0; r

ange

: y�

�3

d.

y�

�x

�3

�v

iv.

dom

ain

: x�

0; r

ange

: y�

0

e.y

��

�x�

iiv.

dom

ain

: x�

3; r

ange

: y�

0

f.y

��

�x

�3

�vi

ivi

.do

mai

n: x

�3;

ran

ge: y

�3

g.y

��

3 �

x�

�3

vivi

i.do

mai

n: x

�3;

ran

ge: y

�0

h.

y�

��

x��

3iii

viii

.do

mai

n: x

��

3; r

ange

: y�

0

2.T

he

grap

h o

f th

e in

equ

alit

y y

��

3x�

6�

is a

sh

aded

reg

ion

. Wh

ich

of

the

foll

owin

gpo

ints

lie

in

side

th

is r

egio

n?

(3, 0

)(2

, 4)

(5, 2

)(4

, �2)

(6, 6

)

(3,0

),(5

,2),

(4,�

2)

Rem

emb

er W

hat

Yo

u L

earn

ed

3.A

good

way

to

rem

embe

r so

met

hin

g is

to

expl

ain

it

to s

omeo

ne

else

. Su

ppos

e yo

u a

rest

udy

ing

this

les

son

wit

h a

cla

ssm

ate

wh

o th

inks

th

at y

ou c

ann

ot h

ave

squ

are

root

fun

ctio

ns

beca

use

eve

ry p

osit

ive

real

nu

mbe

r h

as t

wo

squ

are

root

s. H

ow w

ould

you

expl

ain

th

e id

ea o

f sq

uar

e ro

ot f

un

ctio

ns

to y

our

clas

smat

e?

Sam

ple

an

swer

:To

fo

rm a

sq

uar

e ro

ot

fun

ctio

n,c

ho

ose

eit

her

the

po

siti

ve o

r n

egat

ive

squ

are

roo

t.F

or

exam

ple

,y�

�x�

and

y�

��

x�ar

etw

o s

epar

ate

fun

ctio

ns.

Exam

ple

Lesson 7-3

Cha

pter

721

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-3

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Stud

y Gu

ide

and

Inte

rven

tion

Sq

uar

e R

oo

t F

un

ctio

ns

and

Ineq

ual

itie

sSq

uar

e R

oo

t Fu

nct

ion

sA

fun

ctio

n t

hat

con

tain

s th

e sq

uar

e ro

ot o

f a

vari

able

expr

essi

on i

s a

squ

are

root

fu

nct

ion

.

Gra

ph

y�

�3x

��

2�. S

tate

its

dom

ain

an

d r

ange

.

Sin

ce t

he

radi

can

d ca

nn

ot b

e n

egat

ive,

3x

�2

�0

or x

��2 3� .

Th

e x-

inte

rcep

t is

�2 3� . T

he

ran

ge i

s y

�0.

Mak

e a

tabl

e of

val

ues

an

d gr

aph

th

e fu

nct

ion

.

Gra

ph

eac

h f

un

ctio

n. S

tate

th

e d

omai

n a

nd

ran

ge o

f th

e fu

nct

ion

.

1.y

��

2x�2.

y�

�3�

x�3.

y�

���� 2x �

D:

x

0;R

:y

0

D:

x

0;R

:y

0

D:

x

0;R

:y

0

4.y

�2�

x�

3�

5.y

��

�2x

�3

�6.

y�

�2x

�5

D:

x

3;R

:y

0

D:

x

�3 2� ;R

:y

0

D:

x

��5 2� ;

R:

y

0

y �

��

�2x

� 5

x

y

O

y �

��

��

�2x

� 3

x

y

O

y �

2�

��

x �

3

x

y

O

y �

���x – 2

x

y

Oy

� �

3��x

xy

O

y �

��2x

x

y

O

xy

�2 3�0

11

22

3�

7�

x

y

O

y �

��

��

3x �

2

Exer

cise

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A9

Page 10: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A10 Glencoe Algebra 2

Answers (Lesson 7-3)

Exam

ple

Exer

cise

s

Cha

pter

722

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-3

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Squ

are

Ro

ot

Ineq

ual

itie

sA

squ

are

root

in

equ

alit

yis

an

in

equ

alit

y th

at c

onta

ins

the

squ

are

root

of

a va

riab

le e

xpre

ssio

n. U

se w

hat

you

kn

ow a

bou

t gr

aph

ing

squ

are

root

fun

ctio

ns

and

quad

rati

c in

equ

alit

ies

to g

raph

squ

are

root

in

equ

alit

ies.

Gra

ph

y

�2x

��

1��

2.G

raph

th

e re

late

d eq

uat

ion

y�

�2x

�1

��

2. S

ince

th

e bo

un

dary

sh

ould

be

incl

ude

d, t

he

grap

h s

hou

ld b

e so

lid.

Th

e do

mai

n i

ncl

ude

s va

lues

for

x�

�1 2� , s

o th

e gr

aph

is

to t

he

righ

t

of x

��1 2� .

Gra

ph

eac

h i

neq

ual

ity.

1.y

2�

x�2.

y

�x

�3

�3.

y

3�2x

�1

4.y

3x�

4�

5.y

��

x�

1�

�4

6.y

2�

2x�

3�

7.y

��

3x�

1�

�2

8.y

��

4x�

2�

�1

9.y

2�

2x�

1�

�4

y �

2�

���

2x �

1 �

4 x

y

O

y �

���

�4x

� 2

� 1 x

y

Oy

� �

��

�3x

� 1

� 2

x

y

O

y �

2�

��

�2x

� 3 x

y

Oy

� �

��

x �

1 �

4

x

y

O

y �

���

�3x

� 4

x

y

O

y �

3�

���

2x �

1

x

y

O

y �

��

�x

� 3

x

y

O

y �

2�

�x

x

y

O

x

y

O

y �

��

��

2x �

1 �

2

Stud

y Gu

ide

and

Inte

rven

tion

(con

tinue

d)

Sq

uar

e R

oo

t F

un

ctio

ns

and

Ineq

ual

itie

s

Lesson 7-3

Cha

pter

723

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-3

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Skill

s Pr

actic

eS

qu

are

Ro

ot

Fu

nct

ion

s an

d In

equ

alit

ies

Gra

ph

eac

h f

un

ctio

n. S

tate

th

e d

omai

n a

nd

ran

ge o

f ea

ch f

un

ctio

n.

1.y

��

2x�2.

y�

��

3x�3.

y�

2�x�

D:

x

0,R

:y

0

D:

x

0,R

:y

0

D:

x

0,R

:y

0

4.y

��

x�

3�

5.y

��

�2x

�5

�6.

y�

�x

�4

��

2

D:

x

�3,

R:

y

0D

:x

2.

5,R

:y

0

D:

x

�4,

R:

y

�2

Gra

ph

eac

h i

neq

ual

ity.

7.y

4x�8.

y�

�x

�1

�9.

y�

�4x

�3

x

y

Ox

y

Ox

y

O

x

y

Ox

y

O

x

y

O

x

y

O

x

y

Ox

y

O

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A10

Page 11: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A11 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-3)

Cha

pter

724

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-3

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Gra

ph

eac

h f

un

ctio

n. S

tate

th

e d

omai

n a

nd

ran

ge o

f ea

ch f

un

ctio

n.

1.y

��

5x�2.

y�

��

x�

1�

3.y

�2�

x�

2�

D:

x

0,R

:y

0

D:

x

1,R

:y

0

D:

x

�2,

R:

y

0

4.y

��

3x�

4�

5.y

��

x�

7�

�4

6.y

�1

��

2x�

3�

D:

x

�4 3� ,R

:y

0

D:

x

�7,

R:

y

�4

D:

x

��3 2� ,

R:

y

1

Gra

ph

eac

h i

neq

ual

ity.

7.y

��

�6x�

8.y

��

x�

5�

�3

9.y

2�3x

�2

10.R

OLL

ER C

OA

STER

ST

he

velo

city

of

a ro

ller

coa

ster

as

it m

oves

dow

n a

hil

l is

v

��

v 02

��

64h

�, w

her

e v 0

is t

he

init

ial

velo

city

an

d h

is t

he

vert

ical

dro

p in

fee

t. I

f v

�70

fee

t pe

r se

con

d an

d v 0

�8

feet

per

sec

ond,

fin

d h

.ab

ou

t 75

.6 f

t

11.W

EIG

HT

Use

th

e fo

rmu

la d

���

�39

60, w

hic

h r

elat

es d

ista

nce

fro

m E

arth

d

in m

iles

to

wei

ght.

If

an a

stro

nau

t’s w

eigh

t on

Ear

th W

Eis

148

pou

nds

an

d in

spa

ce W

sis

115

pou

nds

, how

far

fro

m E

arth

is

the

astr

onau

t?ab

ou

t 53

2 m

i

3960

2W

E�

� Ws

x

y O

x

y

O

x

y

O

x

y Ox

y

O

x

y

O

x

y

O

x

y

O

x

y

O

Prac

tice

Sq

uar

e R

oo

t F

un

ctio

ns

and

Ineq

ual

itie

s

Lesson 7-3

Cha

pter

725

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

ATE

____

____

____

__P

ER

IOD

____

_

7-3

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

1.SQ

UA

RES

Cat

hy

is b

uil

din

g a

squ

are

roof

for

her

gar

age.

Th

e ro

of w

ill

occu

py62

5 sq

uar

e fe

et.W

hat

are

th

edi

men

sion

s of

th

e ro

of?

25 f

t b

y 25

ft

2.PE

ND

ULU

MS

Th

e pe

riod

of

ape

ndu

lum

,th

e ti

me

it t

akes

to

com

plet

eon

e sw

ing,

is g

iven

by

the

form

ula

p�

2��

3�w

her

e L

is t

he

len

gth

of

the

pen

dulu

m a

nd

gis

acc

eler

atio

n d

ue

to g

ravi

ty,9

.8 m

/s2 .

Fin

d th

e pe

riod

of

ape

ndu

lum

th

at i

s 0.

65 m

eter

s lo

ng.

Rou

nd

to t

he

nea

rest

ten

th.

1.6

seco

nds

3.R

EFLE

XES

Rac

hel

an

d A

shle

y ar

ete

stin

g on

e an

oth

er’s

ref

lexe

s.R

ach

eldr

ops

a ru

ler

from

a g

iven

hei

ght

so t

hat

it f

alls

bet

wee

n A

shle

y’s

thu

mb

and

inde

x fi

nge

r.A

shle

y tr

ies

to c

atch

th

eru

ler

befo

re i

t fa

lls

thro

ugh

her

han

d.T

he

tim

e re

quir

ed t

o ca

tch

th

e ru

ler

is

give

n b

y t

�w

her

e d

is m

easu

red

infe

et.C

ompl

ete

the

tabl

e.R

oun

d yo

ur

answ

ers

to t

he

nea

rest

hu

ndr

edth

.

4.D

ISTA

NC

EL

ance

is

stan

din

g at

th

esi

de o

f a

road

wat

chin

g a

cycl

ist

go b

y.T

he

dist

ance

bet

wee

n L

ance

an

d th

ecy

clis

t as

a f

un

ctio

n o

f ti

me

is g

iven

by

d�

�9

�3

�6t

2�

.Gra

ph t

his

fu

nct

ion

.F

ind

the

dist

ance

bet

wee

n L

ance

an

dth

e cy

clis

t af

ter

3 se

con

ds.

18.2

5 m

STA

RS

For

Exe

rcis

es 5

-7,u

se t

he

foll

owin

g in

form

atio

n.

Th

e in

ten

sity

of

the

ligh

t fr

om a

n o

bjec

tva

ries

in

vers

ely

wit

h t

he

squ

are

of t

he

dist

ance

.In

oth

er w

ords

,I�

.

5.S

olve

the

equ

atio

n to

fin

d d

in t

erm

s of

I.

d�

��

6.T

wo

star

s gi

ve o

ff t

he

sam

e am

oun

t of

ligh

t.H

owev

er,f

rom

Ear

th t

hei

rin

ten

siti

es d

iffe

r.L

et I

1an

d I 2

be t

hei

rin

ten

siti

es a

nd

let

d1

and

d2

be t

hei

rre

spec

tive

dis

tan

ces

from

Ear

th.W

hat

is

the

rati

o of

d2

to d

1?

��

��

7.If

on

e st

ar a

ppea

rs 9

tim

es a

s in

ten

se

as t

he

oth

er,h

ow m

uch

clo

ser

is i

t to

Ear

th?

3 ti

mes

as

clo

se

I 1I 2

� I 2

d2

� d1

kI � I

k � d2

y

xO

Dis

tan

ce (

in.)

Ref

lex

Tim

e (s

eco

nd

s)

3 in

.0.

136

in.

0.18

9 in

.0.

2212

in.

0.25

�d�

�4

L � gWor

d Pr

oble

m P

ract

ice

Sq

uar

e R

oo

t F

un

ctio

ns

and

Ineq

ual

itie

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A11

Page 12: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A12 Glencoe Algebra 2

Answers (Lessons 7-3 and 7-4)

Cha

pter

726

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-3

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Rea

din

g A

lgeb

raIf

tw

o m

ath

emat

ical

pro

blem

s h

ave

basi

c st

ruct

ura

l si

mil

arit

ies,

th

ey a

re s

aid

to b

e an

alog

ous.

Usi

ng

anal

ogie

s is

on

e w

ay o

fdi

scov

erin

g an

d pr

ovin

g n

ew t

heo

rem

s.

Th

e fo

llow

ing

nu

mbe

red

sen

ten

ces

disc

uss

a t

hre

e-di

men

sion

alan

alog

y to

th

e P

yth

agor

ean

th

eore

m.

01C

onsi

der

a te

trah

edro

n w

ith

th

ree

perp

endi

cula

r fa

ces

that

mee

t at

ver

tex

O.

02S

uppo

se y

ou w

ant

to k

now

how

the

are

as A

, B,a

nd C

ofth

e th

ree

face

s th

at m

eet

at v

erte

x O

are

rela

ted

to t

he

area

Dof

th

e fa

ce o

ppos

ite

vert

ex O

.03

It i

s n

atu

ral

to e

xpec

t a

form

ula

an

alog

ous

to t

he

Pyt

hag

orea

n t

heo

rem

z2

�x2

�y2

, wh

ich

is

tru

e fo

r a

sim

ilar

sit

uat

ion

in

tw

o di

men

sion

s.04

To e

xplo

re t

he

thre

e-di

men

sion

al c

ase,

you

mig

ht

gues

s a

form

ula

an

d th

en t

ry t

o pr

ove

it.

05Tw

o re

ason

able

gu

esse

s ar

e D

3�

A3

�B

3�

C3

and

D2

�A

2�

B2

�C

2 .

Ref

er t

o th

e n

um

ber

ed s

ente

nce

s to

an

swer

th

e q

ues

tion

s.

1.U

se s

ente

nce

01

and

the

top

diag

ram

. Th

e pr

efix

tet

ra-

mea

ns

fou

r. W

rite

an

info

rmal

def

init

ion

of

tetr

ahed

ron

.

a th

ree-

dim

ensi

on

al f

igu

re w

ith

fo

ur

face

s

2.U

se s

ente

nce

02

and

the

top

diag

ram

. Wh

at a

re t

he

len

gth

s of

th

e si

des

ofea

ch f

ace

of t

he

tetr

ahed

ron

?a,

b,a

nd

c;

a,q

,an

d r

;b

,p,a

nd

r;

c,p

,an

d q

3.R

ewri

te s

ente

nce

01

to s

tate

a t

wo-

dim

ensi

onal

an

alog

ue.

Co

nsi

der

a t

rian

gle

wit

h t

wo

per

pen

dic

ula

r si

des

th

at m

eet

at v

erte

x C

.

4.R

efer

to

the

top

diag

ram

an

d w

rite

exp

ress

ion

s fo

r th

e ar

eas

A, B

,an

d C

men

tion

ed i

n s

ente

nce

02.

Po

ssib

le a

nsw

er:

A�

�1 2� pr,

B�

�1 2� pq

,C�

�1 2� rq

5.To

exp

lore

th

e th

ree-

dim

ensi

onal

cas

e, y

ou m

igh

t be

gin

by

expr

essi

ng

a, b

,an

d c

in t

erm

s of

p, q

,an

d r.

Use

th

e P

yth

agor

ean

th

eore

m t

o do

th

is.

a2

�q

2�

r2,b

2�

r2�

p2,c

2�

p2

�q

2

6.W

hic

h g

ues

s in

sen

ten

ce 0

5 se

ems

mor

e li

kely

? Ju

stif

y yo

ur

answ

er.

See

stu

den

ts’e

xpla

nat

ion

s.

y O

z

x

b

c

Op

a

qr

Enri

chm

ent

Lesson 7-4

Cha

pter

727

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Less

on R

eadi

ng G

uide

nth

Ro

ots

Get

Rea

dy

for

the

Less

on

Rea

d t

he

intr

odu

ctio

n t

o L

esso

n 7

-4 i

n y

our

text

boo

k.

Aba

sket

ball

has

a v

olu

me

of a

bou

t 38

2 cu

bic

inch

es. E

xpla

in h

ow y

ou w

ould

fin

d th

e ra

diu

sof

th

e ba

sket

ball

usi

ng

a ca

lcu

lato

r. (

Do

not

act

ual

ly c

alcu

late

th

e ra

diu

s.)

Sam

ple

an

swer

:U

sin

g a

cal

cula

tor,

fin

d t

he

pro

du

ct o

f 3

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nea

rest

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th.

Rea

d t

he

Less

on

1.F

or e

ach

rad

ical

bel

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tify

th

e ra

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and

the

inde

x.

a.3 �

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b.

�15

x2�

radi

can

d:

inde

x:

c.5 �

�34

3�

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can

d:

inde

x:

2.C

ompl

ete

the

foll

owin

g ta

ble.

(D

o n

ot a

ctu

ally

fin

d an

y of

th

e in

dica

ted

root

s.)

Nu

mb

erN

um

ber

of

Po

siti

ve

Nu

mb

er o

f N

egat

ive

Nu

mb

er o

f P

osi

tive

N

um

ber

of

Neg

ativ

eS

qu

are

Ro

ots

Sq

uar

e R

oo

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ub

e R

oo

ts

Cu

be

Ro

ots

271

11

0

�16

00

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3.S

tate

wh

eth

er e

ach

of

the

foll

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g is

tru

eor

fal

se.

a.A

neg

ativ

e n

um

ber

has

no

real

fou

rth

roo

ts.

tru

e

b.

��

121

�re

pres

ents

bot

h s

quar

e ro

ots

of 1

21.

tru

e

c.W

hen

you

tak

e th

e fi

fth

roo

t of

x5 ,

you

mu

st t

ake

the

abso

lute

val

ue

of x

to i

den

tify

the

prin

cipa

l fi

fth

roo

t.fa

lse

Rem

emb

er W

hat

Yo

u L

earn

ed

4.W

hat

is

an e

asy

way

to

rem

embe

r th

at a

neg

ativ

e n

um

ber

has

no

real

squ

are

root

s bu

th

as o

ne

real

cu

be r

oot?

Sam

ple

an

swer

:Th

e sq

uar

e o

f a

po

siti

ve o

r n

egat

ive

nu

mb

er is

po

siti

ve,s

o t

her

e is

no

rea

l nu

mb

er w

ho

se s

qu

are

is n

egat

ive.

Ho

wev

er,t

he

cub

e o

f a

neg

ativ

e n

um

ber

is n

egat

ive,

so a

neg

ativ

en

um

ber

has

on

e re

al c

ub

e ro

ot,

wh

ich

is a

neg

ativ

e n

um

ber

.

5�

343

215

x2

323

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A12

Page 13: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A13 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-4)

Cha

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728

Gle

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Alg

ebra

2

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IOD

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7-4

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Stud

y G

uide

and

Inte

rven

tion

nth

Ro

ots

Sim

plif

y R

adic

als

Sq

uar

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oo

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or a

ny r

eal n

umbe

rs a

and

b, if

a2

�b,

the

n a

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squ

are

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b.

nth

Ro

ot

For

any

rea

l num

bers

aan

d b,

and

any

pos

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inte

ger

n, if

an

�b,

the

n a

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n n

thro

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1.If

nis

eve

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0,

the

n b

has

one

posi

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root

and

one

neg

ativ

e ro

ot.

Rea

l nth

Ro

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of

b,

2.If

nis

odd

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b

0, t

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bha

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n �b�,

�n �

b�3.

If n

is e

ven

and

b

0, t

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bha

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rea

l roo

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nis

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b

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Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Ap

pro

xim

ate

Rad

ical

s w

ith

a C

alcu

lato

r

Irra

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Nu

mb

era

num

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that

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not

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oft

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appr

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Ap

pro

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5 �18

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5 �18

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imat

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th

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eare

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enth

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a m

ile

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hou

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the

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dm

iles

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the

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150

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1100

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Stud

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rven

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(con

tinue

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nth

Ro

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Exer

cise

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A13

Page 14: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A14 Glencoe Algebra 2

Answers (Lesson 7-4)

Cha

pter

730

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____

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IOD

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7-4

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Skill

s Pr

acti

cen

thR

oo

tsU

se a

cal

cula

tor

to a

pp

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7-4

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Use

a c

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lato

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ap

pro

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to t

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e d

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AD

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T TE

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ET

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mal

sen

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mea

sure

an

obj

ect’s

rad

ian

tte

mpe

ratu

re,

wh

ich

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the

amou

nt

of e

ner

gy r

adia

ted

by t

he

obje

ct. T

he

inte

rnal

tem

pera

ture

of

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obje

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lled

its

kin

etic

tem

pera

ture

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for

mul

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Th

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in t

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l th

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the

nea

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29.5

�C

38.H

ERO

’S F

OR

MU

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alva

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ng

fert

iliz

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or h

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of a

ll t

hre

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o fi

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the

area

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A2-A26 A2-07-873977 5/22/06 9:41 AM Page A14

Page 15: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A15 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-4)

Cha

pter

732

Gle

ncoe

Alg

ebra

2

NA

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____

____

____

____

____

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____

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____

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ER

IOD

____

_

7-4

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

1.C

UB

ESC

ath

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bu

ildi

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stor

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tron

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the

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ears

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anob

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tin

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un

wit

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2 ye

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wh

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ency

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the

hig

her

not

e is

twic

e th

e fr

equ

ency

of

the

low

er n

ote.

Cas

ey i

s ex

peri

men

tin

g w

ith

an

inst

rum

ent

that

has

6 n

otes

tu

ned

so

that

th

e fr

equ

ency

of

each

su

cces

sive

not

e in

crea

ses

by t

he

sam

e fa

ctor

an

dth

e fi

rst

and

last

not

e ar

e an

oct

ave

apar

t. B

y w

hat

fac

tor

does

th

e fr

equ

ency

incr

ease

fro

m n

ote

to n

ote?

�52�

or

app

roxi

mat

ely

1.15

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AR

KU

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wh

oles

aler

man

ufa

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rt f

or D

doll

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e w

hol

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er s

ells

the

part

to

a de

aler

for

a P

perc

ent

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kup.

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e de

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sel

ls t

he

part

to

are

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t an

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itio

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tm

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p. T

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iler

in

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ells

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epa

rt t

o it

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kin

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p th

epr

ice

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anot

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rcen

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hat

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pric

e th

at c

ust

omer

s se

e? I

f th

ecu

stom

er b

uys

th

e pa

rt f

or $

80 a

nd

the

mar

kup

is 4

0%, w

hat

app

roxi

mat

ely

was

the

orig

inal

cos

t to

mak

e th

e pa

rt?

D(1

�P

)3; $

29.1

5

PEN

DU

LUM

SF

or E

xerc

ises

5 a

nd

6,

use

th

e fo

llow

ing

info

rmat

ion

.

Mr.

Top

alia

n’s

phys

ics

clas

s is

exp

erim

enti

ngw

ith

pend

ulum

s. T

he c

lass

lea

rned

the

form

ula

T�

2��

3�w

hich

rel

ates

the

ti

me

Tth

at i

t ta

kes

for

a pe

ndul

um t

o sw

ing

back

and

for

th b

ased

on

grav

ity

geq

ual

to32

fee

t pe

r se

cond

squ

ared

, and

the

len

gth

of t

he p

endu

lum

Lin

fee

t.

5.O

ne

grou

p in

th

e cl

ass

mad

e a

2-fo

otlo

ng

pen

dulu

m. U

se t

he

form

ula

to

dete

rmin

e h

ow l

ong

it w

ill

take

for

th

eir

pen

dulu

m t

o sw

ing

back

an

d fo

rth

. 1.

57 s

eco

nds

6.A

not

her

gro

up

deci

ded

they

wan

ted

to m

ake

a pe

ndu

lum

th

at t

ook

abou

t1.

76 s

econ

ds t

o go

bac

k an

d fo

rth

.A

ppro

xim

atel

y h

ow l

ong

shou

ld t

hei

rpe

ndu

lum

be?

2.5

feet

L � g

xx

xWor

d Pr

oble

m P

ract

ice

nth

Ro

ots

Lesson 7-4

Cha

pter

733

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-4

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Exam

ple

7-4

Ap

pro

xim

atin

g S

qu

are

Ro

ots

Con

side

r th

e fo

llow

ing

expa

nsi

on.

(a�� 2b a�

)2�

a2�

�2 2a ab ��

� 4b a2 2�

�a2

�b

�� 4b a2 2�

Th

ink

wh

at h

appe

ns

if a

is v

ery

grea

t in

com

pari

son

to

b. T

he

term

� 4b a2 2�is

ver

y sm

all

and

can

be

disr

egar

ded

in a

n a

ppro

xim

atio

n.

(a�� 2b a�

)2

a2

�b

a�

� 2b a�

�a2

�b

Su

ppos

e a

nu

mbe

r ca

n b

e ex

pres

sed

as a

2�

b, a

b

. Th

en a

n a

ppro

xim

ate

valu

e

of t

he

squ

are

root

is

a�

� 2b a�. Y

ou s

hou

ld a

lso

see

that

a�

� 2b a�

�a2

�b

�.

Use

th

e fo

rmu

la �

a2

��

b��

a�

� 2b a�to

ap

pro

xim

ate

�10

1�

and

�62

2�

.

a.�

101

��

�10

0�

�1�

��

102

��

1�b

.�

622

��

�62

5 �

�3�

��

252

��

3�

Let

a�

10 a

nd

b�

1.L

et a

�25

an

d b

�3.

�10

1�

1

0 �

� 2(1 10

)�

�62

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2

5 �

� 2(3 25

)�

1

0.05

2

4.94

Use

th

e fo

rmu

la t

o fi

nd

an

ap

pro

xim

atio

n f

or e

ach

sq

uar

e ro

ot t

o th

e n

eare

st h

un

dre

dth

. Ch

eck

you

r w

ork

wit

h a

cal

cula

tor.

1.�

626

�25

.02

2.�

99�9.

953.

�40

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5

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94

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441

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00�

1200

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11.

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17.0

312

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260

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.12

13.

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ow t

hat

a�

� 2b a�

�a2

�b

�fo

r a

b

. �a

�� 2b a�

�2�

a2

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�� 4b a2 2�

;

dis

reg

ard

� 4b a2 2�;�a

�� 2b a�

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��

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Enri

chm

ent

Exer

cise

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A15

Page 16: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A16 Glencoe Algebra 2

Answers (Lesson 7-5)

Cha

pter

734

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-5

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Less

on R

eadi

ng G

uide

Op

erat

ion

s w

ith

Rad

ical

Exp

ress

ion

sG

et R

ead

y fo

r th

e Le

sso

nR

ead

th

e in

trod

uct

ion

to

Les

son

7-5

in

you

r te

xtb

ook

.

Des

crib

e h

ow y

ou c

ould

use

th

e go

lden

rat

io t

o fi

nd

the

hei

ght

of a

gol

den

tr

ian

gle

if y

ou k

new

its

wid

th.

Sam

ple

an

swer

:U

se a

cal

cula

tor

to m

ult

iply

th

e w

idth

by

2 an

d d

ivid

e th

e re

sult

by

the

qu

anti

ty o

f �

5 ��

1.R

ou

nd

th

is a

nsw

er t

o t

he

nea

rest

ten

th.

Rea

d t

he

Less

on

1.C

ompl

ete

the

cond

itio

ns t

hat

mus

t be

met

for

a r

adic

al e

xpre

ssio

n to

be

in s

impl

ifie

d fo

rm.

•T

he

nis

as

as p

ossi

ble.

•T

he

con

tain

s n

o (o

ther

th

an 1

) th

at a

re n

th

pow

ers

of a

(n)

or p

olyn

omia

l.

•T

he

radi

can

d co

nta

ins

no

.

•N

o ap

pear

in

th

e .

2.a.

Wh

at a

re c

onju

gate

s of

rad

ical

exp

ress

ion

s u

sed

for?

to r

atio

nal

ize

bin

om

ial

den

om

inat

ors

b.

How

wou

ld y

ou u

se a

con

juga

te t

o si

mpl

ify

the

radi

cal

expr

essi

on

?

Mu

ltip

ly n

um

erat

or

and

den

om

inat

or

by 3

��

2�.c.

In o

rder

to

sim

plif

y th

e ra

dica

l ex

pres

sion

in

par

t b,

tw

o m

ult

ipli

cati

ons

are

nece

ssar

y. T

he m

ulti

plic

atio

n in

the

num

erat

or w

ould

be

done

by

the

met

hod

, an

d th

e m

ult

ipli

cati

on i

n t

he

den

omin

ator

wou

ld b

e do

ne

byfi

ndi

ng

the

of

.

Rem

emb

er W

hat

Yo

u L

earn

ed

3.O

ne w

ay t

o re

mem

ber

som

ethi

ng is

to

expl

ain

it t

o an

othe

r pe

rson

. Whe

n ra

tion

aliz

ing

the

deno

min

ator

in

the

expr

essi

on

, man

y st

uden

ts t

hink

the

y sh

ould

mul

tipl

y nu

mer

ator

and

den

omin

ator

by

. How

wou

ld y

ou e

xpla

in t

o a

clas

smat

e w

hy

this

is

inco

rrec

t

and

wh

at h

e sh

ould

do

inst

ead.

Sam

ple

an

swer

:B

ecau

se y

ou

are

wo

rkin

g w

ith

cub

e ro

ots

,no

t sq

uar

e ro

ots

,yo

u n

eed

to

mak

e th

e ra

dic

and

in t

he

den

om

inat

or

a p

erfe

ct c

ub

e,n

ot

a p

erfe

ct s

qu

are.

Mu

ltip

ly n

um

erat

or

and

den

om

inat

or

by

to m

ake

the

den

om

inat

or

3 �8�,

wh

ich

eq

ual

s 2.

3 �4�

� 3 �4 �

3 �2�

� 3 �2�

1� 3 �

2�

squ

ares

two

dif

fere

nce

FO

IL

1 �

�2�

� 3 �

�2�

den

om

inat

or

rad

ical

s

frac

tio

ns

inte

ger

fact

ors

rad

ican

d

smal

lin

dex

Exam

ple

1Ex

amp

le 2

Lesson 7-5

Cha

pter

735

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-5

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Stud

y G

uide

and

Inte

rven

tion

Op

erat

ion

s w

ith

Rad

ical

Exp

ress

ion

sSi

mp

lify

Rad

ical

Exp

ress

ion

s

For

any

rea

l num

bers

aan

d b,

and

any

inte

ger

n

1:

Pro

du

ct P

rop

erty

of

Rad

ical

s1.

if n

is e

ven

and

aan

d b

are

both

non

nega

tive,

the

n n �

ab��

n �a�

�n �

b�.2.

if n

is o

dd,

then

n �

ab��

n �a�

�n �

b�.

To s

impl

ify

a sq

uar

e ro

ot, f

ollo

w t

hes

e st

eps:

1.F

acto

r th

e ra

dica

nd

into

as

man

y sq

uar

es a

s po

ssib

le.

2.U

se t

he

Pro

duct

Pro

pert

y to

iso

late

th

e pe

rfec

t sq

uar

es.

3.S

impl

ify

each

rad

ical

.

Qu

oti

ent

Pro

per

ty o

f R

adic

als

For

any

rea

l num

bers

aan

d b

�0,

and

any

inte

ger

n

1,

n ���

, if

all r

oots

are

def

ined

.

To e

lim

inat

e ra

dica

ls f

rom

a d

enom

inat

or o

r fr

acti

ons

from

a r

adic

and,

mu

ltip

ly t

he

nu

mer

ator

an

d de

nom

inat

or b

y a

quan

tity

so

that

th

e ra

dica

nd

has

an

exa

ct r

oot.

n �a�

� n �b �

a � b

Sim

pli

fy

3 ��

16a

�5 b

7�

.3 �

�16

a�

5 b7

��

3 �(�

2)3

��

2 �

a�

3�

a2�

�(b

2 )3

��

b�

��

2ab2

3 �2a

2 b�

Sim

pli

fy

.

���

Quo

tient

Pro

pert

y

�F

acto

r in

to s

quar

es.

�P

rodu

ct P

rope

rty

�S

impl

ify.

��

Rat

iona

lize

the

deno

min

ator

.

�S

impl

ify.

2|x|

�10

xy�

��

15y3

�5y�

� �5y�

2|x|

�2x�

� 3y2 �

5y�

2|x|

�2x�

� 3y2 �

5y�

�(2

x)2

��

�2x�

��

�(3

y2 )2

��

�5y�

�(2

x)2

��

2x��

��

(3y2 )

2�

�5y

�8x

3�

� �45

y5�

8x3

� 45y5

8x3

� 45y5

Sim

pli

fy.

1.5 �

54�15

�6�

2.4 �

32a9

b�

20 �2a

2 | b5 |

4 �2a�

3.�

75x4

y�

7 �5x

2 y3�

3y�

4.��

5.��

6.3 ��

pq

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p2

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3�40

| a3| b

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�� 14

a6 b3

�98

6�5�

�25

36 � 125

Exer

cise

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A16

Page 17: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A17 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-5)

Exam

ple

1

Exam

ple

2

Cha

pter

736

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-5

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Op

erat

ion

s w

ith

Rad

ical

sW

hen

you

add

exp

ress

ion

s co

nta

inin

g ra

dica

ls, y

ou c

anad

d on

ly l

ike

term

s or

lik

e ra

dic

al e

xpre

ssio

ns.

Tw

o ra

dica

l ex

pres

sion

s ar

e ca

lled

lik

era

dic

al e

xpre

ssio

ns

if b

oth

th

e in

dice

s an

d th

e ra

dica

nds

are

ali

ke.

To m

ult

iply

rad

ical

s, u

se t

he

Pro

duct

an

d Q

uot

ien

t P

rope

rtie

s. F

or p

rodu

cts

of t

he

form

(a

�b�

�c�

d�)�

(e�

f��

g�h�)

, use

th

e F

OIL

met

hod

. To

rati

onal

ize

den

omin

ator

s, u

se

con

juga

tes.

Nu

mbe

rs o

f th

e fo

rm a

�b�

�c�

d�an

d a�

b��

c�d�,

wh

ere

a, b

, c, a

nd

dar

era

tion

al n

um

bers

, are

cal

led

con

juga

tes.

Th

e pr

odu

ct o

f co

nju

gate

s is

alw

ays

a ra

tion

aln

um

ber.

Sim

pli

fy 2

�50�

�4�

500

��

6�12

5�

.

2�50�

�4�

500

��

6�12

5�

�2�

52�

2�

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102

�5

��

6�52

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acto

r us

ing

squa

res.

�2

�5

��

2��

4 �

10 �

�5�

�6

�5

��

5�S

impl

ify s

quar

e ro

ots.

�10

�2�

�40

�5�

�30

�5�

Mul

tiply

.

�10

�2�

�10

�5�

Com

bine

like

rad

ical

s.

Stud

y G

uide

and

Inte

rven

tion

(con

tinue

d)

Op

erat

ion

s w

ith

Rad

ical

Exp

ress

ion

s

Sim

pli

fy (2

�3�

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2�)(�

3��

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.

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6 �

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pli

fy

.

��

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5��

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6 �

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9 �

5

6 �

2 �5�

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2�

��

32�

(�5� )

2

3 �

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� 3 �

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2 �

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2 �

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2 �

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pli

fy.

1.3 �

2��

�50�

�4�

8�2.

�20�

��

125

��

�45�

3.�

300

��

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��

75�

04�

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3�

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3 �24�

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3 �12�

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2�3�(

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63 �

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Page 18: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A18 Glencoe Algebra 2

Answers (Lesson 7-5)

Cha

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738

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6x2 y

and

9x2 y

. Use

th

e P

yth

agor

ean

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eore

m t

o fi

nd

asi

mpl

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d ex

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th

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739

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7-5

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1.C

UB

ESC

ath

y h

as a

rec

tan

gula

r bo

xw

ith

dim

ensi

ons

20 i

nch

es b

y 35

in

ches

by 4

0 in

ches

. Sh

e w

ould

lik

e to

rep

lace

it

wit

h a

box

in

th

e sh

ape

of a

cu

be b

ut

wit

h t

he

sam

e vo

lum

e. W

hat

sh

ould

th

ele

ngt

h o

f a

side

of

the

cube

be?

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ress

you

r an

swer

as

a ra

dica

l ex

pres

sion

in

sim

ples

t fo

rm.

10�3

28�in

.

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YSI

CS

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e sp

eed

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e tr

avel

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y w

her

e t

is

the

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sion

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stri

ng

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te t

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on i

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est

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e fr

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ency

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the

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the

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pian

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the

rati

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equ

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f tw

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otes

that

are

9 s

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.

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and

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d1

and

a br

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in

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ples

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rm.

RA

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GF

or E

xerc

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5 a

nd

6, u

se t

he

foll

owin

g in

form

atio

n a

nd

exp

ress

you

ran

swer

s in

sim

ple

st f

orm

.

Joh

n i

s Ja

y’s

you

nge

r br

oth

er. T

hey

lik

e to

race

an

d, a

fter

man

y ra

ces,

th

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oun

d th

atth

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ires

t ra

ce w

as t

o ru

n s

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tly

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tdi

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ey b

oth

sta

rt a

t th

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me

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n s

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ght

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0.2

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es. T

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gure

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hn

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ctly

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Jay

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, exa

ctly

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tes

wou

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t ta

ke t

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each

to

run

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ile?

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rm.

Joh

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A2-A26 A2-07-873977 5/22/06 9:41 AM Page A18

Page 19: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A19 Glencoe Algebra 2

An

swer

s

Answers (Lessons 7-5 and 7-6)

Exam

ple

1

Exam

ple

2

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s

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7-5

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Sp

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7-6

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Less

on R

eadi

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uide

Rat

ion

al E

xpo

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tsG

et R

ead

y fo

r th

e Le

sso

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trod

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to

Les

son

7-6

in

you

r te

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ook

.

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for

mul

a in

the

int

rodu

ctio

n co

ntai

ns t

he e

xpon

ent

. Wha

t do

you

thi

nk

it m

igh

t m

ean

to

rais

e a

nu

mbe

r to

th

e po

wer

?

Sam

ple

an

swer

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e th

e fi

fth

ro

ot

of

the

nu

mb

er a

nd

sq

uar

e it

.

Rea

d t

he

Less

on

1.C

ompl

ete

the

foll

owin

g de

fin

itio

ns

of r

atio

nal

exp

onen

ts.

•F

or a

ny

real

nu

mbe

r b

and

for

any

posi

tive

in

tege

r n

, b� n1 �

�ex

cept

wh

en b

and

nis

.

•F

or a

ny

non

zero

rea

l n

um

ber

b, a

nd

any

inte

gers

man

d n

, wit

h n

,

b�m n��

, exc

ept

wh

en b

and

nis

.

2.C

ompl

ete

the

con

diti

ons

that

mu

st b

e m

et i

n o

rder

for

an

exp

ress

ion

wit

h r

atio

nal

expo

nen

ts t

o be

sim

plif

ied.

•It

has

no

expo

nen

ts.

•It

has

no

expo

nen

ts i

n t

he

.

•It

is

not

a

frac

tion

.

•T

he

of a

ny

rem

ain

ing

is t

he

nu

mbe

r po

ssib

le.

3.M

arga

rita

an

d P

ierr

e w

ere

wor

kin

g to

geth

er o

n t

hei

r al

gebr

a h

omew

ork.

On

e ex

erci

se

aske

d th

em t

o ev

alu

ate

the

expr

essi

on 2

7�4 3� . Mar

gari

ta t

hou

ght

that

th

ey s

hou

ld r

aise

27

to

the

fou

rth

pow

er f

irst

an

d th

en t

ake

the

cube

roo

t of

th

e re

sult

. Pie

rre

thou

ght

that

they

sh

ould

tak

e th

e cu

be r

oot

of 2

7 fi

rst

and

then

rai

se t

he

resu

lt t

o th

e fo

urt

h p

ower

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hos

e m

eth

od i

s co

rrec

t?B

oth

met

ho

ds

are

corr

ect.

Rem

emb

er W

hat

Yo

u L

earn

ed

4.S

ome

stu

den

ts h

ave

trou

ble

rem

embe

rin

g w

hic

h p

art

of t

he

frac

tion

in

a r

atio

nal

expo

nen

t gi

ves

the

pow

er a

nd

wh

ich

par

t gi

ves

the

root

. How

can

you

r kn

owle

dge

ofin

tege

r ex

pon

ents

hel

p yo

u t

o ke

ep t

his

str

aigh

t?S

amp

le a

nsw

er:

An

inte

ger

ex

po

nen

t ca

n b

e w

ritt

en a

s a

rati

on

al e

xpo

nen

t.F

or

exam

ple

,23

�2�3 1� .

You

kn

ow

th

at t

his

mea

ns

that

2 is

rai

sed

to

th

e th

ird

po

wer

,so

th

en

um

erat

or

mu

st g

ive

the

po

wer

,an

d,t

her

efo

re,t

he

den

om

inat

or

mu

stg

ive

the

roo

t.

leas

tra

dic

alin

dexco

mp

lex

den

om

inat

or

frac

tio

nal

neg

ativ

e

even

�0

(n �b�)

mn �

bm �

1

even

�0

n �b �

2 � 5

2 � 5

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A19

Page 20: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A20 Glencoe Algebra 2

Answers (Lesson 7-6)

Exam

ple

1

Cha

pter

742

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

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AT

E__

____

____

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ER

IOD

____

_

7-6

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Stud

y G

uide

and

Inte

rven

tion

Rat

ion

al E

xpo

nen

tsR

atio

nal

Exp

on

ents

an

d R

adic

als

Def

init

ion

of

b� n1 �

For

any

rea

l num

ber

ban

d an

y po

sitiv

e in

tege

r n,

b�1 n��

n �b�,

exc

ept

whe

n b

0

and

nis

eve

n.

Def

init

ion

of

b�m n�

For

any

non

zero

rea

l num

ber

b, a

nd a

ny in

tege

rs m

and

n, w

ith n

1,

b�m n��

n �bm �

�(n �

b�)m

, ex

cept

whe

n b

0

and

nis

eve

n.

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te 2

8�1 2�in

rad

ical

for

m.

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ice

that

28

0.

28�1 2�

��

28��

�22

�7

��

�22 �

��

7��

2�7�

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luat

e �

��1 3� .

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ice

that

�8

0,

�12

5

0, a

nd

3 is

odd.

���1 3�

� ��

2� �

53 ��

8�

� 3 ��

125

��

8� �

125

�8

� �12

5

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te e

ach

exp

ress

ion

in

rad

ical

for

m.

1.11

�1 7�

2.15

�1 3�

3.30

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7 �11�

3 �15�

3000

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te e

ach

rad

ical

usi

ng

rati

onal

exp

onen

ts.

4.�

47�5.

3 �3a

5 b2

�6.

4 �16

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3 �

2�1 4��

p�5 4�

Eva

luat

e ea

ch e

xpre

ssio

n.

7.�

27�2 3�

8.9.

(0.0

004)

�1 2�

90.

021 � 105�

�1 2�

� 2�5�

2 � 5

Exam

ple

2

Exer

cise

s

Exam

ple

1Ex

amp

le 2

Lesson 7-6

Cha

pter

743

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-6

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Sim

plif

y Ex

pre

ssio

ns

All

th

e pr

oper

ties

of

pow

ers

from

Les

son

6-1

app

ly t

o ra

tion

alex

pon

ents

. Wh

en y

ou s

impl

ify

expr

essi

ons

wit

h r

atio

nal

exp

onen

ts, l

eave

th

e ex

pon

ent

inra

tion

al f

orm

, an

d w

rite

th

e ex

pres

sion

wit

h a

ll p

osit

ive

expo

nen

ts. A

ny

expo

nen

ts i

n t

he

den

omin

ator

mu

st b

e po

siti

ve i

nte

gers

.

Wh

en y

ou s

impl

ify

radi

cal

expr

essi

ons,

you

may

use

rat

ion

al e

xpon

ents

to

sim

plif

y, b

ut

you

ran

swer

sh

ould

be

in r

adic

al f

orm

. Use

th

e sm

alle

st i

nde

x po

ssib

le.

Stud

y G

uide

and

Inte

rven

tion

(con

tinue

d)

Rat

ion

al E

xpo

nen

ts

Sim

pli

fy y

�2 3��

y�3 8� .

y�2 3��

y�3 8��

y�2 3��

�3 8��

y�2 25 4�

Sim

pli

fy

4 �14

4x6

�.

4 �14

4x6

��

(144

x6)�1 4�

�(2

4�

32�

x6)�1 4�

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2 )�1 4�

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6 )�1 4�

�2

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�x�3 2�

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�(3

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�2x

�3x�

Sim

pli

fy e

ach

exp

ress

ion

.

1.x�4 5�

�x�6 5�

2.� y�2 3� ��3 4�

3.p�4 5�

�p� 17 0�

x2

y�1 2�

p�3 2�

4.� m

��6 5� ��2 5�

5.x�

�3 8��

x�4 3�6.

� s��1 6� ��

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or

x�2 23 4�

s�2 9�

7.8.

� a�2 3� ��6 5�

�� a

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p�2 3�

a2

or

10.

6 �12

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11.

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125

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.6 �

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� x��1 3�

p � p�1 3�

m�1 23 5�

�� m

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Exer

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s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A20

Page 21: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A21 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-6)

Cha

pter

744

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-6

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Skill

s Pr

acti

ceR

atio

nal

Exp

on

ents

Wri

te e

ach

exp

ress

ion

in

rad

ical

for

m.

1.3�1 6�

6 �3�

2.8�1 5�

5 �8�

3.12

�2 3�3 �

122

�o

r (3 �

12�)2

or

2�3

18�4.

(s3 )

�3 5�s

5 �s4 �

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te e

ach

rad

ical

usi

ng

rati

onal

exp

onen

ts.

5.�

51�51

�1 2�6.

3 �37�

37�1 3�

7.4 �

153

�15

�3 4�8.

3 �6x

y2�

6�1 3� x�1 3� y

�2 3�

Eva

luat

e ea

ch e

xpre

ssio

n.

9.32

�1 5�2

10.8

1�1 4�3

11.2

7��1 3�

12.4

��1 2�

13.1

6�3 2�64

14.(

�24

3)�4 5�

81

15.2

7�1 3��

27�5 3�

729

16. �

��3 2�

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pli

fy e

ach

exp

ress

ion

.

17.c

�1 52 ��

c�3 5�c

318

.m�2 9�

�m

�1 96 �m

2

19.� q

�1 2� �3q

�3 2�20

.p�

�1 5�o

r

21.x

�� 16 1�

or

22.

x� 15 2�

23.

or

24.

or

25.

12 �64�

�2�

26.

8 �49

a8b

�2 �

| a|4 �

7b�n�2 3�

� n1 � n

�1 3�

n�1 3�

� n�1 6�

�n

�1 2�

y�1 4�

� y1 � y

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y��1 2�

� y�1 4�

x�2 3�

� x�1 4�

x� 15 1�

� x1 � x

� 16 1�

p�4 5�

� p1 � p

�1 5�8 � 274 � 9

1 � 21 � 3

Lesson 7-6

Cha

pter

745

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-6

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Wri

te e

ach

exp

ress

ion

in

rad

ical

for

m.

1.5�1 3�

2.6�2 5�

3.m

�4 7�4.

(n3 )�2 5�

3 �5�

5 �62 �

or

(5 �6�)

27 �

m4

�o

r (7 �

m�)4

n5 �

n�

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te e

ach

rad

ical

usi

ng

rati

onal

exp

onen

ts.

5.�

79�6.

4 �15

3�

7.3 �

27m

6 n�

4 �8.

5�2a

10b

79�1 2�

153�1 4�

3m2 n

�4 3�5

�2�1 2�

| a5

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luat

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xpre

ssio

n.

9.81

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10.1

024�

�1 5�11

.8�

�5 3�

12.�

256�

�3 4��

13.(

�64

)��2 3�

14.2

7�1 3��

27�4 3�

243

15. �

��2 3�16

.17

.� 25�1 2� �� �

64�

�1 3� � �

Sim

pli

fy e

ach

exp

ress

ion

.

18.g

�4 7��

g�3 7�g

19.s

�3 4��

s�1 43 �s

420

.� u�

�1 3� ���4 5�

u� 14 5�

21.y

��1 2�

or

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��3 5�

or

23.

q�1 5�

24.

25.

26.10 �

85 �2�

2�27

.�12�

�5 �

123

�28

.4 �

6��

34 �

6�29

.

1210 �

12�3�

6�

30.E

LEC

TRIC

ITY

Th

e am

oun

t of

cu

rren

t in

am

pere

s I

that

an

app

lian

ce u

ses

can

be

calc

ula

ted

usi

ng

the

form

ula

I�

���1 2� , w

her

e P

is t

he

pow

er i

n w

atts

an

d R

is t

he

resi

stan

ce i

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hm

s. H

ow m

uch

cu

rren

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es a

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ance

use

if

P�

500

wat

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nd

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s? R

oun

d yo

ur

answ

er t

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e n

eare

st t

enth

.7.

1 am

ps

31.B

USI

NES

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com

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at p

rodu

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DV

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use

s th

e fo

rmu

la C

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calc

ula

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hat

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the

com

pan

y’s

cost

to p

rodu

ce 1

50 D

VD

s pe

r da

y? R

oun

d yo

ur

answ

er t

o th

e n

eare

st d

olla

r.$7

98

P � R

a�3b�

�3b

a� �

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2z�

2z�1 2�

��

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5 � 416 � 49

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6

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tice

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ion

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xpo

nen

ts

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A21

Page 22: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A22 Glencoe Algebra 2

Answers (Lesson 7-6)

Cha

pter

746

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-6

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

1.SQ

UA

RIN

G T

HE

CU

BE

Acu

be h

as s

ide

len

gth

s. W

hat

is

the

side

len

gth

of

the

squ

are

that

has

an

are

a eq

ual

to

the

volu

me

of t

his

cu

be?

Wri

te y

our

answ

eru

sin

g ra

tion

al e

xpon

ents

.

s�3 2�

2.W

ATE

R T

OW

ERA

larg

e w

ater

tow

erst

ores

dri

nki

ng

wat

er i

n a

big

sph

eric

alta

nk.

Th

e m

ayor

of

the

tow

n d

ecid

esth

at t

he

wat

er t

ower

m

ust

be

repl

aced

w

ith

a l

arge

r ta

nk.

Tow

n r

esid

ents

in

sist

that

th

e n

ew t

ower

be

a s

pher

e. I

f th

en

ew t

ank

wil

l h

old

10 t

imes

as

mu

chw

ater

as

the

old

tan

k, h

ow m

any

tim

es l

ong

shou

ld

the

radi

us

of t

he

new

tan

k be

com

pare

dto

th

e ol

d ta

nk?

Wri

te y

our

answ

eru

sin

g ra

tion

al e

xpon

ents

.

10�1 3�

3.B

ALL

OO

NS

Asp

her

ical

bal

loon

is

bein

g in

flat

ed f

aste

r an

d fa

ster

. Th

evo

lum

e of

th

e ba

lloo

n a

s a

fun

ctio

n o

fti

me

is 9

�t2

. Wh

at i

s th

e ra

diu

s of

th

eba

lloo

n a

s a

fun

ctio

n o

f ti

me?

Wri

te y

our

answ

er u

sin

g ra

tion

al e

xpon

ents

.

3 ()�2 3�

4.IN

TER

EST

Rit

a op

ened

a b

ank

acco

un

tth

at a

ccu

mu

late

d in

tere

st a

t th

e ra

te o

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pou

nde

d an

nu

ally

. Her

mon

eyac

cum

ula

ted

inte

rest

in

th

at a

ccou

nt

for

8 ye

ars.

Sh

e th

en t

ook

all

of h

er m

oney

out

of t

hat

acc

oun

t an

d pl

aced

it

into

anot

her

acc

oun

t th

at p

aid

5% i

nte

rest

com

pou

nde

d an

nu

ally

. Aft

er 4

yea

rs,

she

took

all

of

her

mon

ey o

ut

of t

hat

acco

un

t. W

hat

sin

gle

inte

rest

rat

e w

hen

com

pou

nde

d an

nu

ally

wou

ld g

ive

her

the

sam

e ou

tcom

e fo

r th

ose

12 y

ears

?R

oun

d yo

ur

answ

er t

o th

e n

eare

sth

un

dred

th o

f a

perc

ent.

2.32

%

CEL

LSF

or E

xerc

ises

5-7

, use

th

efo

llow

ing

info

rmat

ion

.

Th

e n

um

ber

of c

ells

in

a c

ell

cult

ure

gro

ws

expo

nen

tial

ly. T

he

nu

mbe

r of

cel

ls i

n t

he

cult

ure

as

a fu

nct

ion

of

tim

e is

giv

en b

y th

e ex

pres

sion

N()

tw

her

e t

is m

easu

red

in

hou

rs a

nd

Nis

th

e in

itia

l si

ze o

f th

ecu

ltu

re.

5.A

fter

3 h

ours

, th

ere

wer

e 17

28 c

ells

in

the

cult

ure

. Wh

at i

s N

?10

00

6.H

ow m

any

cell

s w

ere

in t

he

cult

ure

afte

r 20

min

ute

s? E

xpre

ss y

our

answ

erin

sim

ples

t fo

rm.

200

�15

0�1 3�

7.H

ow m

any

cell

s w

ere

in t

he

cult

ure

afte

r 2.

5 h

ours

? E

xpre

ss y

our

answ

er i

nsi

mpl

est

form

.

288

�30

�1 2�6 � 5

t � 2

Wor

d Pr

oble

m P

ract

ice

Rat

ion

al E

xpo

nen

ts

Lesson 7-6

Cha

pter

747

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-6

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Les

ser-

Kn

ow

n G

eom

etri

c F

orm

ula

sM

any

geom

etri

c fo

rmu

las

invo

lve

radi

cal

expr

essi

ons.

Mak

e a

dra

win

g to

ill

ust

rate

eac

h o

f th

e fo

rmu

las

give

n o

n t

his

pag

e.

Th

en e

valu

ate

the

form

ula

for

th

e gi

ven

val

ue

of t

he

vari

able

. Rou

nd

an

swer

s to

th

e n

eare

st h

un

dre

dth

.

Enri

chm

ent

1.T

he

area

of

an i

sosc

eles

tri

angl

e. T

wo

side

s h

ave

len

gth

a; t

he

oth

er s

ide

has

len

gth

c. F

ind

Aw

hen

a�

6 an

d c

�7.

A�

� 4c � �4a

2�

�c2 �

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17.0

6 u

nit

s2

3.T

he

area

of

a re

gula

r pe

nta

gon

wit

h a

side

of

len

gth

a. F

ind

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hen

a�

4.

A�

�a 42 ��

25 �

�10

�5�

�A

�27

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un

its2

5.T

he

volu

me

of a

reg

ula

r te

trah

edro

nw

ith

an

edg

e of

len

gth

a. F

ind

Vw

hen

a

�2.

V�

� 1a 23 ��

2�

V�

0.94

un

its3

7.H

eron

’s F

orm

ula

for

th

e ar

ea o

f a

tria

ngl

e u

ses

the

sem

i-pe

rim

eter

s,

wh

ere

s�

�a�

2b�

c�

. Th

e si

des

of t

he

tria

ngl

e h

ave

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ind

Aw

hen

a�

3, b

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an

d c

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s�

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he

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quil

ater

al t

rian

gle

wit

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gth

a. F

ind

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a�

8.

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3�

A�

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he

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r h

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on w

ith

asi

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h a

. Fin

d A

wh

en a

�9.

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A�

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nit

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6.T

he

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curv

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urf

ace

of a

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ht

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e w

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alt

itu

de o

f h

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us

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se r

. Fin

d S

wh

en r

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and

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entr

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gle

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s th

e se

mi-

peri

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A2-A26 A2-07-873977 5/22/06 9:41 AM Page A22

Page 23: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A23 Glencoe Algebra 2

An

swer

s

Answers (Lessons 7-6 and 7-7)

Exam

ple

Cha

pter

748

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-6

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Spre

adsh

eet

Act

ivit

yA

pp

reci

atio

n a

nd

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ate

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r th

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itia

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n A

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r th

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ract

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r th

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lue

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e.

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th

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lls

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play

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nts

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adsh

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ecia

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l am

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mal

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Exer

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s

Lesson 7-7

Cha

pter

749

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-7

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Less

on R

eadi

ng G

uide

So

lvin

g R

adic

al E

qu

atio

ns

and

Ineq

ual

itie

sG

et R

ead

y fo

r th

e le

sso

nR

ead

th

e in

trod

uct

ion

to

Les

son

7-7

in

you

r te

xtb

ook

.

Exp

lain

how

you

wou

ld u

se t

he

form

ula

in

you

r te

xtbo

ok t

o fi

nd

the

cost

of

prod

ucin

g12

5,00

0 co

mpu

ter

chip

s. (

Des

crib

e th

e st

eps

of t

he c

alcu

lati

on in

the

ord

er in

whi

ch y

ou w

ould

perf

orm

the

m, b

ut d

o no

t ac

tual

ly d

o th

e ca

lcul

atio

n.)

Sam

ple

an

swer

:R

aise

125

,000

to

th

e p

ow

er b

y ta

kin

g t

he

cub

e ro

ot

of

125,

000

and

sq

uar

ing

th

e re

sult

(o

r ra

ise

125,

000

to t

he

po

wer

by

ente

rin

g 1

25,0

00 ^

(2/

3) o

n a

cal

cula

tor)

.

Mu

ltip

ly t

he

nu

mb

er y

ou

get

by

10 a

nd

th

en a

dd

150

0.

Rea

d t

he

Less

on

1.a.

Wh

at i

s an

ext

ran

eou

s so

luti

onof

a r

adic

al e

quat

ion

?S

amp

le a

nsw

er:

a n

um

ber

that

sat

isfi

es a

n e

qu

atio

n o

bta

ined

by

rais

ing

bo

th s

ides

of

the

ori

gin

aleq

uat

ion

to

a h

igh

er p

ow

er b

ut

do

es n

ot

sati

sfy

the

ori

gin

al e

qu

atio

n

b.

Des

crib

e tw

o w

ays

you

can

ch

eck

the

prop

osed

sol

uti

ons

of a

rad

ical

equ

atio

n i

n o

rder

to d

eter

min

e w

het

her

an

y of

th

em a

re e

xtra

neo

us

solu

tion

s.S

amp

le a

nsw

er:

On

ew

ay is

to

ch

eck

each

pro

po

sed

so

luti

on

by

sub

stit

uti

ng

it in

to t

he

ori

gin

al e

qu

atio

n.A

no

ther

way

is t

o u

se a

gra

ph

ing

cal

cula

tor

to g

rap

hb

oth

sid

es o

f th

e o

rig

inal

eq

uat

ion

.See

wh

ere

the

gra

ph

s in

ters

ect.

Th

is c

an h

elp

yo

u id

enti

fy s

olu

tio

ns

that

may

be

extr

aneo

us.

2.C

ompl

ete

the

step

s th

at s

hou

ld b

e fo

llow

ed i

n o

rder

to

solv

e a

radi

cal

ineq

ual

ity.

Ste

p 1

If t

he

of t

he

root

is

, ide

nti

fy t

he

valu

es o

f

the

vari

able

for

wh

ich

th

e is

.

Ste

p 2

Sol

ve t

he

alge

brai

call

y.

Ste

p 3

Test

to

ch

eck

you

r so

luti

on.

Rem

emb

er W

hat

Yo

u L

earn

ed

3.O

ne

way

to

rem

embe

r so

met

hin

g is

to

expl

ain

it

to a

not

her

per

son

. Su

ppos

e th

at y

our

frie

nd

Leo

ra t

hin

ks t

hat

sh

e do

es n

ot n

eed

to c

hec

k h

er s

olu

tion

s to

rad

ical

equ

atio

ns

bysu

bsti

tuti

on b

ecau

se s

he

know

s sh

e is

ver

y ca

refu

l an

d se

ldom

mak

es m

ista

kes

in h

erw

ork.

How

can

you

exp

lain

to

her

th

at s

he

shou

ld n

ever

thel

ess

chec

k ev

ery

prop

osed

solu

tion

in

th

e or

igin

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quat

ion

?S

amp

le a

nsw

er:

Sq

uar

ing

bo

th s

ides

of

aneq

uat

ion

can

pro

du

ce a

n e

qu

atio

n t

hat

is n

ot

equ

ival

ent

to t

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gin

alo

ne.

Fo

r ex

amp

le,t

he

on

ly s

olu

tio

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f x

�5

is 5

,bu

t th

e sq

uar

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x2

�25

has

tw

o s

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5 an

d �

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valu

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ual

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ive

rad

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d

even

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2 � 3

2 � 3

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A23

Page 24: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A24 Glencoe Algebra 2

Answers (Lesson 7-7)

Exam

ple

1Ex

amp

le 2

Cha

pter

750

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-7

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Stud

y G

uide

and

Inte

rven

tion

So

lvin

g R

adic

al E

qu

atio

ns

and

Ineq

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itie

sSo

lve

Rad

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Eq

uat

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sT

he

foll

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g st

eps

are

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sol

vin

g eq

uat

ion

s th

at h

ave

vari

able

s in

th

e ra

dica

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e al

gebr

aic

proc

edu

res

may

be

nee

ded

befo

re y

ou u

se t

hes

est

eps.

Ste

p 1

Isol

ate

the

radi

cal o

n on

e si

de o

f th

e eq

uatio

n.S

tep

2To

elim

inat

e th

e ra

dica

l, ra

ise

each

sid

e of

the

equ

atio

n to

a p

ower

equ

al t

o th

e in

dex

of t

he r

adic

al.

Ste

p 3

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ve t

he r

esul

ting

equa

tion.

Ste

p 4

Che

ck y

our

solu

tion

in th

e or

igin

al e

quat

ion

to m

ake

sure

that

you

hav

e no

t obt

aine

d an

y ex

tran

eous

roo

ts.

Sol

ve 2

�4x

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8.

2�4x

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dd 4

to

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e th

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l.

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8 �

36S

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om e

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.

x�

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ivid

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ch s

ide

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.

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eck

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ecks

.

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ve �

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plify

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the

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��

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ve e

ach

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.

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Cha

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ncoe

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ebra

2

NA

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____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-7

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Solv

e R

adic

al In

equ

alit

ies

Ara

dic

al i

neq

ual

ity

is a

n i

neq

ual

ity

that

has

a v

aria

ble

in a

rad

ican

d. U

se t

he

foll

owin

g st

eps

to s

olve

rad

ical

in

equ

alit

ies.

Ste

p 1

If th

e in

dex

of t

he r

oot

is e

ven,

iden

tify

the

valu

es o

f th

e va

riabl

e fo

r w

hich

the

rad

ican

d is

non

nega

tive.

Ste

p 2

Sol

ve t

he in

equa

lity

alge

brai

cally

.S

tep

3Te

st v

alue

s to

che

ck y

our

solu

tion.

Sol

ve 5

��

20x

��

4�

�3.

Stud

y G

uide

and

Inte

rven

tion

(con

tinue

d)

So

lvin

g R

adic

al E

qu

atio

ns

and

Ineq

ual

itie

s

Sin

ce t

he

radi

can

d of

a s

quar

e ro

otm

ust

be

grea

ter

than

or

equ

al t

oze

ro, f

irst

sol

ve20

x�

4 �

0.20

x�

4 �

020

x�

�4

x�

�1 � 5

Now

sol

ve 5

��

20x

��

4��

�3.

5 �

�20

x�

�4�

��

3O

rigin

al in

equa

lity

�20

x�

�4�

�8

Isol

ate

the

radi

cal.

20x

�4

�64

Elim

inat

e th

e ra

dica

l by

squa

ring

each

sid

e.

20x

�60

Sub

trac

t 4

from

eac

h si

de.

x�

3D

ivid

e ea

ch s

ide

by 2

0.

It a

ppea

rs t

hat

��

x�

3 is

th

e so

luti

on. T

est

som

e va

lues

.

x�

�1

x�

0x

�4

�20

(�1

�)

�4

�is

not

a r

eal

5 �

�20

(0)

��

4�

�3,

so

the

5 �

�20

(4)

��

4�

4.2,

so

num

ber,

so t

he in

equa

lity

isin

equa

lity

is s

atis

fied.

th

e in

equa

lity

is n

otno

t sa

tisfie

d.sa

tisfie

d

Th

eref

ore

the

solu

tion

��

x�

3 ch

ecks

.

Sol

ve e

ach

in

equ

alit

y.

1.�

c�

2�

�4

�7

2.3�

2x�

1�

�6

15

3.�

10x

��

9��

2

5

c

11

x�

5x

4

4.5

3 �x

�2

��

8

25.

8 �

�3x

�4

��

36.

�2x

�8

��

4

2

x�

6�

x

7

x

14

7.9

��

6x�

3�

�6

8.�

49.

2�5x

�6

��

1

5

x

1x

8

x

�3

10.�

2x�

1�

2��

4 �

1211

.�2d

��

1��

�d�

�5

12.4

�b

�3

��

�b

�2

��

10

x

260

d

4

b

6

6 � 51 � 2

20�

��

3x�

1�4 � 3

1 � 2

1 � 5

1 � 5

Exam

ple

Exer

cise

s

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A24

Page 25: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A25 Glencoe Algebra 2

An

swer

s

Answers (Lesson 7-7)

Cha

pter

752

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

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ER

IOD

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7-7

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Skill

s Pr

acti

ceS

olv

ing

Rad

ical

Eq

uat

ion

s an

d In

equ

alit

ies

Sol

ve e

ach

eq

uat

ion

or

ineq

ual

ity.

1.�

x��

525

2.�

x��

3 �

716

3.5�

j��1

4.v�1 2�

�1

�0

no

so

luti

on

5.18

�3y

�1 2��

25n

o s

olu

tio

n6.

3 �2w�

�4

32

7.�

b�

5�

�4

218.

�3n

��

1��

58

9.3 �

3r�

6�

�3

1110

.2 �

�3p

��

7��

63

11.�

k�

4�

�1

�5

4012

.(2

d�

3)�1 3�

�2

13.(

t�

3)�1 3�

�2

1114

.4 �

(1 �

7u)�1 3�

�0

�9

15.�

3z�

2�

��

z�

4�

no

so

luti

on

16.�

g�

1�

��

2g�

�7�

8

17.�

x�

1�

�4�

x�

1�

no

so

luti

on

18.5

��

s�

3�

�6

3

s

4

19.�

2 �

�3x

�3

7�

1

x�

2620

.��

2a�

�4�

��

6�

2

a

16

21.2

�4r

�3

10r

7

22.4

��

3x�

1�

3

x�

0

23.�

y�

4�

�3

�3

y

3224

.�3�

11r

��

3��

�15

r

23 � 11

1 � 3

5 � 2

1 � 25

Lesson 7-7

Cha

pter

753

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-7

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Sol

ve e

ach

eq

uat

ion

or

ineq

ual

ity.

1.�

x��

864

2.4

��

x��

31

3.�

2p��

3 �

104.

4�3h�

�2

�0

5.c�1 2�

�6

�9

96.

18 �

7h�1 2�

�12

no

so

luti

on

7.3 �

d�

2�

�7

341

8.5 �

w�

7�

�1

8

9.6

�3 �

q�

4�

�9

3110

.4 �

y�

9�

�4

�0

no

so

luti

on

11.�

2m�

�6�

�16

�0

131

12.

3 �4m

��

1��

2 �

2

13. �

8n�

�5�

�1

�2

14.�

1 �

4�

t��8

��

6�

15.�

2t�

5�

�3

�3

16.(

7v�

2)�1 4�

�12

�7

no

so

luti

on

17.(

3g�

1)�1 2�

�6

�4

3318

.(6u

�5)

�1 3��

2 �

�3

�20

19.�

2d�

�5�

��

d�

1�

420

.�4r

�6

��

�r�

2

21.�

6x�

4�

��

2x�

1�

0�22

.�2x

�5

��

�2x

�1

�n

o s

olu

tio

n

23.3

�a�

�12

a

1624

.�z

�5

��

4 �

13�

5

z

76

25.8

��

2q��

5n

o s

olu

tio

n26

.�2a

��

3�

5

a�

14

27.9

��

c�

4�

�6

c

528

.3 �

x�

1�

2x

��

7

29.S

TATI

STIC

SS

tati

stic

ian

s u

se t

he

form

ula

��

�v�

to c

alcu

late

a s

tan

dard

dev

iati

on �

,w

her

e v

is t

he

vari

ance

of

a da

ta s

et. F

ind

the

vari

ance

wh

en t

he

stan

dard

dev

iati

on

is 1

5.22

5

30.G

RA

VIT

ATI

ON

Hel

ena

drop

s a

ball

fro

m 2

5 fe

et a

bove

a l

ake.

Th

e fo

rmu

la

t�

�25

��

h�de

scri

bes

the

tim

e t

in s

econ

ds t

hat

th

e ba

ll i

s h

feet

abo

ve t

he

wat

er.

How

man

y fe

et a

bove

th

e w

ater

wil

l th

e ba

ll b

e af

ter

1 se

con

d?9

ft

1 � 4

3 � 2

7 � 2

41 � 2

3 � 47 � 4

63 � 4

1 � 1249 � 2

Prac

tice

S

olv

ing

Rad

ical

Eq

uat

ion

s an

d In

equ

alit

ies

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A25

Page 26: Answers (Anticipation Guide and Lesson 7-1) · Chapter 7 A1 Glencoe Algebra 2 Answers Answers (Anticipation Guide and Lesson 7-1) STEP 1 Chapter 7 3 ... STEP 1 STEP 2 why you disagree

Chapter 7 A26 Glencoe Algebra 2

Answers (Lesson 7-7)

Cha

pter

754

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-7

Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

1.SI

GN

SA

sign

pai

nte

r m

ust

spe

nd

$8n

�2 3��

400

to

mak

e n

sign

s.

How

man

ysi

gns

can

th

e pa

inte

r m

ake

for

$120

0?10

00

2.LA

TER

AL

AR

EAT

he

late

ral

area

of

aco

ne

wit

h b

ase

radi

us

ran

d h

eigh

t h

isgi

ven

by

the

form

ula

L�

�r�

r2�

h�

2 �.

Aco

ne

has

a l

ater

al a

rea

of 6

5�sq

uar

eu

nit

s an

d a

base

rad

ius

of 5

un

its.

Wh

at i

s th

e h

eigh

t of

th

e co

ne?

12 u

nit

s

3.O

RIG

AM

IG

eorg

ia w

ants

to

fold

asq

uar

e pi

ece

of p

aper

in

to a

n e

quil

ater

altr

ian

gle.

Sh

e w

ants

to

loca

te t

he

dist

ance

xu

p th

e si

de o

f th

e sq

uar

ew

her

e sh

e ca

n m

ake

the

fold

in

dica

ted

by t

he

dash

ed l

ine

in t

he

figu

re s

o th

at

a�

b. F

rom

geo

met

ry c

lass

, sh

e kn

ows

that

a�

�1

�x2

�an

d b

��

2�(1

�x)

. S

o th

e eq

uat

ion

sh

e m

ust

sol

ve i

s �

1 �

x2�

��

2�(1

�x)

. Wh

at i

s x?

2 �

�3�

4.TE

THER

SA

teth

er i

s be

ing

atta

ched

to

a 2

5-fo

ot p

ole

in s

uch

a w

ay t

hat

x

�y

�50

. By

the

Pyt

hag

orea

nT

heo

rem

, th

e di

stan

ce y

��

x2�

2�

52 �.

Wh

at m

ust

xbe

?

18.7

5 ft

RA

NG

E F

or E

xerc

ises

5 a

nd

6, u

se t

he

foll

owin

g in

form

atio

n.

An

ast

eroi

d is

pas

sin

g n

ear

Ear

th. I

f E

arth

is l

ocat

ed a

t th

e or

igin

of

a co

ordi

nat

epl

ane,

th

e pa

th t

hat

th

e as

tero

id w

ill

trac

e

out

is g

iven

by

y�

, x

0.

On

e u

nit

corr

espo

nds

to o

ne m

illi

on m

iles

. Car

l le

arns

that

he

wil

l be

abl

e to

see

the

ast

eroi

d w

ith

his

tele

scop

e w

hen

the

aste

roid

is

wit

hin

mil

lion

mil

es o

f E

arth

.

5.W

rite

an

exp

ress

ion

th

at g

ives

th

edi

stan

ce o

f th

e as

tero

id f

rom

Ear

th a

s a

fun

ctio

n o

f x.

�11

11�x2 �

6.F

or w

hat

val

ues

of

xw

ill

the

aste

roid

be

in r

ange

of

Car

l’s t

eles

cope

?

x

12

17 � 12

289

� x2

145

� 12

17 � x

25 ft

y

x

b

xa 1

45˚

h

r

Wor

d Pr

oble

m P

ract

ice

Rat

ion

al E

qu

atio

ns

and

Ineq

ual

itie

s

Exam

ple

Lesson 7-7

Cha

pter

755

Gle

ncoe

Alg

ebra

2

NA

ME

____

____

____

____

____

____

____

____

____

____

____

__D

AT

E__

____

____

__P

ER

IOD

____

_

7-7

Copyright ©Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Enri

chm

ent

Tru

th T

able

sIn

mat

hem

atic

s, t

he

basi

c op

erat

ion

s ar

e ad

diti

on, s

ubt

ract

ion

, mu

ltip

lica

tion

, di

visi

on, f

indi

ng

a ro

ot, a

nd

rais

ing

to a

pow

er. I

n l

ogic

, th

e ba

sic

oper

atio

ns

are

the

foll

owin

g: n

ot(�

), a

nd

(�

), o

r (

), a

nd

impl

ies

(→).

If p

and

qar

e st

atem

ents

, th

en �

pm

ean

s n

ot p

; �q

mea

ns

not

q; p

� q

mea

ns

pan

d q;

p

qm

ean

s p

or q

; an

d p

→ q

mea

ns

pim

plie

s q.

Th

e op

erat

ion

s ar

e de

fin

ed b

y tr

uth

tab

les.

On

th

e le

ft b

elow

is

the

tru

th t

able

for

th

e st

atem

ent

�p.

Not

ice

that

th

ere

are

two

poss

ible

con

diti

ons

for

p, t

rue

(T)

or f

alse

(F

). I

f p

is t

rue,

�p

is f

alse

; if

pis

fal

se, �

pis

tru

e. A

lso

show

n a

re t

he

tru

th t

able

s fo

r p

� q

, p

q, a

nd

p →

q.

p�

pp

qp

� q

pq

p

qp

qp

→ q

TF

TT

TT

TT

TT

TF

TT

FF

TF

TT

FF

FT

FF

TT

FT

TF

FF

FF

FF

FT

You

can

use

th

is i

nfo

rmat

ion

to

fin

d ou

t u

nde

r w

hat

con

diti

ons

a co

mpl

ex

stat

emen

t is

tru

e.

Un

der

wh

at c

ond

itio

ns

is �

p

qtr

ue?

Cre

ate

the

tru

th t

able

for

th

e st

atem

ent.

Use

th

e in

form

atio

n f

rom

th

e tr

uth

ta

ble

abov

e fo

r p

q

to c

ompl

ete

the

last

col

um

n.

pq

�p

�p

q

TT

FT

Wh

en o

ne

stat

emen

t is

T

FF

Ftr

ue

and

on

e is

fal

se,

FT

TT

the

con

jun

ctio

n is

tru

e.F

FT

T

The

tru

th t

able

indi

cate

s th

at �

p

qis

tru

e in

all

case

s ex

cept

whe

re p

is t

rue

and

qis

fal

se.

Use

tru

th t

able

s to

det

erm

ine

the

con

dit

ion

s u

nd

er w

hic

h e

ach

sta

tem

ent

is t

rue.

1.�

p

�q

2.�

p →

(p →

q)

all e

xcep

t w

her

e b

oth

all

pan

d q

are

tru

e3.

(p

q)

(�p

� �

q)4.

(p →

q)

(q

→ p

)al

lal

l

5.(p

→ q

)�

(q →

p)

6.(�

p �

�q)

→ �

(p

q)b

oth

pan

d q

are

tru

e;al

lb

oth

pan

d q

are

fals

e

A2-A26 A2-07-873977 5/22/06 9:41 AM Page A26