mth 3-14a mth 4-14a mth 4-14b 9-jun-15created by mr. lafferty maths dept. simplifying algebraic...
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MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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. Understand and be able Understand and be able too simplify simple too simplify simple algebraic expressions by algebraic expressions by collecting ‘ like terms.’collecting ‘ like terms.’
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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 )
MTH 3-14aMTH 4-14aMTH 4-14b
RuleMultiply the numbers
together
multiply the letters together.
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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. We are learning how to multiply out simply algebraic brackets.
AlgebraAlgebra
2.2. Apply multiplication Apply multiplication rules rules for positive and for positive and negative negative numbers numbers when removing when removing brackets.brackets.
Removing brackets
3(b + 5) =3b + 15
Example 1
4(w - 2) =4w - 8
Example 2
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Removing aRemoving aSingle BracketSingle BracketMTH 3-14a
MTH 4-14aMTH 4-14b
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2(y - 1) =2y - 2
Example 3
7(w - 6) =7w- 42
Example 4
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Removing aRemoving aSingle BracketSingle BracketMTH 3-14a
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8(x + 3) =8x+ 24
Example 5
4(3 -2m) = 12 - 8m
Example 6
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Removing aRemoving aSingle BracketSingle BracketMTH 3-14a
MTH 4-14aMTH 4-14b
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Example 7 : Write down an expressionfor the amount indicate belowin two difference ways.
3(x + 3) =3x + 9
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Removing aRemoving aSingle BracketSingle Bracket
x+3
x+3
x+3
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Example 8 : Write down an expressionfor the amount indicate belowin two difference ways.
5(y - 2) = 5y - 10
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Removing aRemoving aSingle BracketSingle Bracket
y-2
y-2 y-2
y-2y-2
MTH 3-14aMTH 4-14aMTH 4-14b
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18 Apr 202318 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.
Removing bracketsMTH 3-14aMTH 4-14aMTH 4-14b
= 4(y + 5)
(i) A = L x B
(ii) = 4(y + 5)= 4y + 20
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww
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1. We are learning how to remove brackets and simplify.
1. Understand how to remove brackets
AlgebraAlgebraRemoving Brackets & Simplifying
2. Understand the need to show clear working.
3. Apply to context questions.
a(b + 5) =ab + 5a
Example 1
p(w - 2) =pw - 2p
Example 2
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Removing aRemoving aSingle BracketSingle BracketMTH 3-14a
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y(y - 1) = y2 - y
Example 3
7w(w - 3) =7w2 - 21w
Example 4
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Removing aRemoving aSingle BracketSingle BracketMTH 3-14a
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a(a2 + 3b) =a3 + 3ab
Example 5
y2(3y -2c) =3y3 - 2cy2
Example 6
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Removing aRemoving aSingle BracketSingle BracketMTH 3-14a
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-(x + y) = -x - y
Example 7
-5(a - 7) =-5a + 35
Example 8
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Removing aRemoving aSingle BracketSingle BracketMTH 3-14a
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7 + 3(4 - y) =7 + 12
Example 9
9 - 3(8 - y) =9 - 24
Example 10
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Removing aRemoving aSingle BracketSingle Bracket
- 3y= 19 - 3y
+ 3y
Tidy Up
= -15 + 3y
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Tidy Up
A = 10(x – 2)
Example 11
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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
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Example 12 : Find area of the orange border
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Removing aRemoving aSingle BracketSingle Bracket
(x - 2)10
x
12 Area =Big Rec – Small Rec
= 12x – 10(x - 2)
= 12x
= 2x + 20
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-10x+ 20
4(m - 3) - (m + 2) =4m - 12 - m - 2
Example 13
Example 14
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= 3m - 14
7(y - 1) - 2(y + 4) =7y - 7 - 2y - 8 = 5y - 15
Tidy Up
Removing Two Single Removing Two Single BracketsBrackets
MTH 3-14aMTH 4-14aMTH 4-14b
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Tidy Up
Calculate difference if
y = 14
Diff = 3 x 14 – 8= 34
A = 4(y – 5)
Example 15 : Find an expression for the difference inthe areas.
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(y - 5)
47 A = 7(y - 4)
(y - 4)Difference = 7(y - 4) - 4(y – 5)
= 7y - 28= 3y - 8
Removing Two Single Removing Two Single BracketsBrackets
MTH 3-14aMTH 4-14aMTH 4-14b
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- 4y + 20
Calculate difference if
x = 4
Diff = 2 x 4 + 20
=28
A = 7(x + 1)
Example 16 : Find an expression for the difference inthe areas.
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(x + 1)
79 A = 9(x + 3)
x + 3Difference = 9(x + 3) - 7(x + 1) = 9x + 27
= 2x + 20
Removing Two Single Removing Two Single BracketsBrackets
MTH 3-14aMTH 4-14aMTH 4-14b
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– 7x - 7
As= 4(x - 3)
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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.
4x-3
Removing Brackets & SimplifyingMTH 3-14aMTH 4-14aMTH 4-14b
Ab= 6x
= 4x
As= 6x - 4(x - 3)= 6x = 2x + 12
- 12
- 4x+ 12
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww
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1. We are learning how to evaluate an expression.
1. Be able to substitute numbers for letters in an expression.
AlgebraAlgebra
2. Use previous knowledge of Number to evaluate a expression.
Evaluating Expressions – number for letter
18 Apr 202318 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 = -1BODMAS
MTH 3-14aMTH 4-14aMTH 4-14b
2a + c
= 2x3 + (-1)
= 2x3 - 1= 6 - 1
= 5
b2 – a2
= 42 – 32
= 16 – 9
= 7
2b2
= 2x(4)2
= 2x16
= 32
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
2a2 + 3b + 30c
= 2x(3)2 + 3x4 + 30x(-1)
= 18 + 12 - 30
= 0
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 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)
MTH 3-14aMTH 4-14aMTH 4-14b
18 Apr 202318 Apr 2023 Created by Mr. Lafferty Maths Dept.Created by Mr. Lafferty Maths Dept.ww
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1. We are learning the process of factorising’.
1. Understand the term factorising.
AlgebraAlgebra
2. Apply previous knowledge to recognise the HCF for a set of values.
Factorising – The Common Factor
3. Analysis answer to validate it is correct.
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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
= 5 3( x + 5 )
Check by multiplying out the bracket to get back to where
you started
MTH 3-14aMTH 4-14aMTH 4-14b
= x3x3
153
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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
2x( 2x - 3y )
Factorise 4x2 – 6xy
Check by multiplying out the bracket to get back to where
you started
MTH 3-14aMTH 4-14aMTH 4-14b
= 2x4x2
2x= 3y
6xy2x
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AlgebraAlgebra
Simply find the HCF for a given set of data and write the data using brackets :-
Factorising – The Common FactorMTH 3-14aMTH 4-14aMTH 4-14b
6x – 12
= ( )6 x - 2
8a – 12b
= ( )4 2a - 3b
18 Apr 202318 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 FactorMTH 3-14aMTH 4-14aMTH 4-14b
am + an
= ( )a m+ n
9f – 6f2
= ( )3f 3 - 2f
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FactorisingFactorising
Factorise the following :
(a) 3x + 6
(b) 4xy – 2x
(c) 6a + 7a2
(d) y2 - y
MTH 3-14aMTH 4-14aMTH 4-14b
= ( )3 x+ 2
= ( )2x 2y- 1
= ( )a 6 + 7a
= ( )y y - 1
18 Apr 202318 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
MTH 3-14aMTH 4-14aMTH 4-14b