SWBAT…interpret the meaning of slope (rate of change) Mon, 12/13

Agenda

1. WU (10 min)

2. Review hw#1 (10 min)

3. Slope as rate of change – 4 examples (25 min)

Warm-Up:

1.) Write the hw in your planner for the week

2.) Find the value of r so that the line through (r, 6) and (10, -3) has a slope of -3/2.

3.) A horizontal lines passes through (2, 5). What other

point does the line contain? A.(2,3) B.(0,5) C.(5,10) D.(0,2)

HW2: Slopes of lines

SWBAT…interpret the meaning of slope (rate of change) 1st: Tues, 12/14

Agenda

1. WU – back of agenda problems (10 min)

2. Review back of agenda problems (5 min)

3. Slope interpretations – hw#2 (30 min)

Warm-Up:

1.) Do the back of this week’s agenda problems

HW2: Slopes interpretations / Quiz tomorrow

SWBAT…interpret the meaning of slope (rate of change) 2nd: Tues, 12/14

Agenda

1. Review back of agenda problems (10 min)

2. Slope interpretations-hw#2 (15 min)

3. Slope-intercept form (20 min)

Warm-Up:

1.) Take out back of agenda problems

2.) Take out hw#1: Slope

HW2: Slopes interpretations / Quiz tomorrow

Examples with slope as the Examples with slope as the rate of changerate of change

Example 1:

Find the rate of change. Explain what the rate of change means.

Points Scored for 3-point Baskets

0

3

6

9

12

15

18

21

0 1 2 3 4 5 6 7

Number of Baskets

Po

ints

Sco

red

1. What is the slope of the line? 2. What is the meaning of the slope?3. What is the y-intercept?4. What is the x-intercept? 5. Write the equation of the line.

Gallons of water used in a shower

4, 24

3, 18

2, 12

1, 6

0

5

10

15

20

25

0 1 2 3 4

Minutes

Gal

lon

s

Example 2:

1) What is the slope of the line from 0 to 400 minutes?

-What does this mean?

2) What is the slope of the line from 400 to 800 minutes?

-What does this mean?

100 200 300 400 500 600 700 800

Minutes on the phone (minutes)

80

60

40

20

Fee ($)

Example 3:

Example 4:Sam had 5 gallons of gasoline in his bike.  After driving 100 miles, he had 3 gallons left. 

a. Find the slope of the lineb. What does this slope tell us?

Slope as the rate of changeSlope as the rate of change

a. Find the slope of the line    Slope = rise/run = -2/100 = -1/50

   b.  What does this slope tell us?Since -1/50 = -0.02, we know that Sam’s bike is burning 0.02 gallons of gasoline for every mile that he travels.   (The negative value of the slope tells us that the amount of gasoline in the tank is decreasing.)

Non-Linear EquationsNon-Linear Equations

http://en.wikipedia.org/wiki/File:Graph_of_sliding_derivative_line.gif

Work on hw#2: Interpreting slope & intercepts for 15 minutes…

Afterwards, we will move on to slope-intercept form

1.) What is the slope? 2.) What is the meaning of the slope?3.) What is the y-intercept (write as an ordered pair) 4.) What is the meaning of the y-intercept?5.) Write the equation of the line (y = mx + b).

Total Cost of Cellular Phone Service

4.905.005.105.205.305.405.505.605.705.80

0 1 2 3 4 5 6 7

Minutes

Do

llars

HW#2: Interpreting Slope & Intercepts

2.) Cost per day3.) Cost per printBack1.)E2.) A3.) B48.) C49) D