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16 Mar 2022 16 Mar 2022 Created by Mr. Lafferty Maths Dept. Created by Mr. Lafferty Maths Dept. Simplifying Algebraic Expression Removing Brackets Algebra Algebra www.mathsrevision.com Removing Brackets & Simplifying Evaluating Expressions Factorising – The common factor

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19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Simplifying Algebraic Expressions

Removing Brackets

AlgebraAlgebraw

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Removing Brackets & Simplifying

Evaluating Expressions

Factorising – The common factor

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Starter QuestionsStarter Questionsw

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1. A TV has been reduced in the sale

by 20%. I t was £250. How much is it now.

3. 30% of £300

4. Tidy up the expression

5y + 3d +4d + 10y

5. Find the area and

2. Simplif y the ratio 16:64

perimeter of the shape.6cm

2cm

2cm

3cm

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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1.1. To remember the To remember the phrase phrase

‘ ‘ like terms.’like terms.’

1. To review tidying up expressions.

AlgebraAlgebraSimplifying Algebraic Expressions

2.2. To be able to simplify To be able to simplify simple algebraic simple algebraic expressions by collecting ‘ expressions by collecting ‘ like terms.’like terms.’

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebraSimplifying Algebraic Expressions

Reminder !We can only add and subtract “ like terms “

x x x x 4x9 7p p 2p

10 6 1w 3 6a b a b

2 2 2x x x

2 7a b9 6w

23x

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebraSimplifying Algebraic Expressions

Reminder !Multiplying terms

7 a 7a5w 5w

2 4m m b b 2b

28m

( NOT 2b )

( NOT 8m )

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebraSimplifying Algebraic Expressions

y 2

y

2

Question : Find the area of each of the 3 sections of this shape. What is the total area.

1 2A y 2A y y

3 2A y

2y

2y

2y

2 2 2TA y y y 2 4y y

1 2 3

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Now try Exercise 1Ch11 (page 46)

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AlgebraAlgebraSimplifying Algebraic Expressions

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Starter QuestionsStarter Questionsw

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1. Find the perimeter and area of the shape.

3. Find all the missing angles.

2. Calculate (a) (-3m) x (-4m) (b) (2b) x (3a)

6h

2a

100o

60o

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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1.1. Understand the key steps Understand the key steps in removing brackets.in removing brackets.

1. To explain how to multiply out simply algebraic brackets.

AlgebraAlgebra

2.2. Apply multiplication Apply multiplication rules rules for integers numbers for integers numbers when when removing brackets.removing brackets.

Removing brackets

3(b + 5) =3b + 15

Example 1

4(w - 2) =4w - 8

Example 2

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

2(y - 1) =2y - 2

Example 3

7(w - 6) =7w- 42

Example 4

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

8(x + 3) =8x+ 24

Example 5

4(3 -2m) = 12 - 8m

Example 6

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

Example 7 : Write down an expressionfor the amount indicate belowin two difference ways.

3(x + 3) =3x + 9

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

x+3

x+3

x+3

Example 8 : Write down an expressionfor the amount indicate belowin two difference ways.

5(y - 2) = 5y - 10

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

y-2

y-2 y-2

y-2y-2

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebra

Y + 5

4

Question : Find the area of the rectangle (i) With brackets(ii) Without brackets.

(i) 4( 5)A y

(ii) 4( 5)A y 4 20y

Removing brackets

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Now try Exercise 2Ch11 (page 48)

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AlgebraAlgebra Removing brackets

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Starter QuestionsStarter Questionsw

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1. My shape has 2 pairs of parallel lines

and equal angles and lengths.

What is my shape?

1 12. Calculate of

2 4

3. Remove brackets 4(5d - 6)

4. Calculate the area of the rectangle.

7cm

(x+2)cm

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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1. Explain how to remove brackets and simplify.

1. Understand how to remove brackets

AlgebraAlgebraRemoving Brackets & Simplifying

3. Tidy up after removing brackets.

2. Apply rules integer numbers.

a(b + 5) =ab + 5a

Example 1

p(w - 2) =pw - 2p

Example 2

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

y(y - 1) = y2 - y

Example 3

7w(w - 3) =7w2 - 21w

Example 4

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

a(a2 + 3b) =a3 + 3ab

Example 5

y2(3y -2c) =3y3 - 2cy2

Example 6

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

-(x + y) = -x - y

Example 7

-5(a - 7) =-5a + 35

Example 8

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

7 + 3(4 - y) =7 + 12

Example 9

9 - 3(8 - y) =9 - 24

Example 10

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

- 3y= 19 - 3y

Tidy Up

+ 3y

Tidy Up

= -15 + 3y

A = 10(x – 2)

Example 11

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

Find my Area (x - 2)

10

Find my Areax

12

A = 12x

A = L x B A = L x B

Example 12 : Find area of the orange border

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

Removing aRemoving aSingle BracketSingle Bracket

(x - 2)10

x

12

Area =Big Rec – Small Rec

= 12x – 10(x - 2)

= 12x – 10x + 20

= 2x + 20

4(m - 3) - (m + 2) =4m - 12 - m - 2

Example 13

Example 14

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

= 3m - 14

Tidy Up

7(y - 1) - 2(y + 4) =7y - 7 - 2y - 8 = 5y - 15

Tidy Up

Removing Two Single Removing Two Single BracketsBrackets

3 x 14 – 8= 34

A = 4(y – 5)

Example 15 : Find an expression for the difference inthe areas.

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

(y - 5)

47 A = 7(y- 4)

(y- 4)Difference = 7(y - 4) - 4(y – 5)

= 7y - 28 - 4y + 20= 3y - 8

Calculate difference if

y = 14

Removing Two Single Removing Two Single BracketsBrackets

2 x 4 + 20=28

A = 7(x + 1)

Example 16 : Find an expression for the difference inthe areas.

Apr 19, 2023Apr 19, 2023 Created by Mr. Created by Mr. [email protected]@mathsrevision.com

(x + 1)

79 A = 9(x + 3)

x + 3Difference = 9(x + 3) - 7(x + 1) = 9x + 27 – 7x - 7

= 2x + 20

Calculate difference if

x = 4

Removing Two Single Removing Two Single BracketsBrackets

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AlgebraAlgebra

x

6

Question : Find the area of the large rectangle, then the small rectangle and hence find the area of the red section.

6LA x 4( 3)SA x 4 12x

4x-3

6 (4 12)RA x x 2 12x

Removing Brackets & Simplifying

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Now try Exercise 3Ch11 (page 50)

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AlgebraAlgebraRemoving Brackets & Simplifying

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Starter QuestionsStarter Questionsw

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1. My shape has 2 pairs of parallel lines

equal lengths and opposite angles are equal.

What is my shape?

1 12. Calculate of

3 4

3. Remove brackets and simplif y 4e- (8e -12)

4. Calculate the perimeter of the rectangle.

7cm

(x+2)cm

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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1. To show how to evaluate an expression given values for the letters.

1. Be able to substitute numbers for letters in an expression.

AlgebraAlgebra

2. Use previous knowledge to evaluate expression.

Evaluating Expressions – number for letter

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebraEvaluating Expressions – number for letter

Given the following information find the values of :-

a = 3 ; b = 4 and c = -1

BODMAS

5 a 5 3 15 2a c 2 3 ( 1)

22b

2 2b a (4 4) (3 3)

2 4 4

516 9 7

2 b b 32

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebraEvaluating Expressions – number for letter

Given the following information find the values of :-

a = 3 ; b = 4 and c = -1

25c 5 ( 1) ( 1) 5 c c 5

22 3 30a b c

(2 3 3) (3 4) (30 ( 1)) (2 ) (3 ) (30 )a a b c

18 12 30 0

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Now try Exercise 4Ch2 (page 51)

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AlgebraAlgebraEvaluating Expressions – number for letter

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Starter QuestionsStarter Questionsw

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angles and adjcent lengths are equal.

What is my shape?

2. Find the highest common f actor f or

(a) 12 and 24 (b) 2x and 10x

3. Calculate 6a+ 5ab when a=(-1) b=(-2)

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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1. To show how to reverse the process of removing bracket ‘factorising’.

1. Be able to recognise the HCF for set of values.

AlgebraAlgebra

2. Understand the term factorising.

Factorising – The Common Factor

3. Factorise simple expressions.

19 Apr 202319 Apr 2023 Created by Mr. [email protected] by Mr. [email protected]

FactorisingFactorisingw

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Example Factorise 3x + 15

1. Find the HCF for 3x and 15 3

2. HCF goes outside the bracket 3( )

3. To see what goes inside the bracketdivide each term by HCF

3x ÷ 3 = x 15 ÷ 3 = 5 3( x + 5 )

Check by multiplying out the bracket to get back to where

you started

S3 Credit

19 Apr 202319 Apr 2023 Created by Mr. [email protected] by Mr. [email protected]

FactorisingFactorisingw

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Example

1. Find the HCF for 4x2 and 6xy 2x

2. HCF goes outside the bracket 2x( )

3. To see what goes inside the bracketdivide each term by HCF

4x2 ÷ 2x =2x 6xy ÷ 2x = 3y 2x( 2x- 3y )

Factorise 4x2 – 6xy

Check by multiplying out the bracket to get back to where

you started

S3 Credit

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebra

Simply find the HCF for a given set of data and write the data using brackets :-

Factorising – The Common Factor

6 12x

HCF ?6

6( )x 2

8 12a b

HCF ?4

4( )2a 3b

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww

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AlgebraAlgebra

Simply find the HCF for a given set of data and write the data using brackets :-

Factorising – The Common Factor

am an

HCF ?a

( )a m n

29 6x x

HCF ?3x

3 ( )x 3 2x

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FactorisingFactorising

Factorise the following :

(a) 3x + 6

(b) 4xy – 2x

(c) 6a + 7a2

(d) y2 - y

3(x + 2)

2x(2y – 1)

a(6 + 7a)

y(y – 1)

Be careful !

S3 Credit

19 Apr 202319 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.

Now try Exercise 5Ch11 (page 54)

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AlgebraAlgebraFactorising – The Common Factor