1. Created by Mr. Lafferty@mathsrevision.com
Factors S3
Credit
Factors
Example : Find the factors of 56.
Numbers that divide into 56 without leaving a remainder
F56 = 1 and 56
2 and 28
4 and 14
7 and
28-Mar-17
Created by Mr.

2. Factors Highest Common Factor Largest Same Number
Credit
Highest Common Factor
Highest
Common
Factor
Largest
Same
Number
We need to write out all factor pairs in order to find
the Highest Common Factor.
28-Mar-17
Created by Mr.

3. Created by Mr. Lafferty@mathsrevision.com
Factors S3
Credit
Highest Common Factor
Example : Find the HCF of 8 and 12.
F8 = 1 and 8
2 and 4
F12 = 1 and 12
2 and 6
3 and 4
HCF = 4
28-Mar-17
Created by Mr.

4. Created by Mr. Lafferty@mathsrevision.com
Factors S3
Credit
Highest Common Factor
Example : Find the HCF of 4x and x2.
F4x = 1, and 4x
Fx2 = 1 and x2
2 and 2x
x and x
4 and x
HCF = x
Example : Find the HCF of 5 and 10x.
F5 = 1 and 5
F10x = 1, and 10x
2 and 5x
HCF = 5
5 and 2x
28-Mar-17
Created by Mr.
10 and x

5. Created by Mr. Lafferty@mathsrevision.com
Factors S3
Credit
Highest Common Factor
Example : Find the HCF of ab and 2b.
F ab = 1 and ab
a and b
F2b = 1 and 2b
2 and b
HCF = b
Example : Find the HCF of 2h2 and 4h.
F 2h2 = 1 and 2h2
2 and h2 , h and 2h
F4h = 1 and 4h
2 and 2h
4 and h
HCF = 2h
28-Mar-17
Created by Mr.

6. Created by Mr. Lafferty@mathsrevision.com
Factors S3
Credit
Find the HCF for these terms 8w
(a) 16w and 24w
9y2 and 6y
(c) 4h and 12h2
(d) ab2 and a2b 3y 4h ab
28-Mar-17
Created by Mr.

7. Factorising Example Factorise 3x + 15 1. Find the HCF for 3x and 15 3
Check by multiplying out the bracket to get back to where you started
Factorising S3
Credit
Example
Factorise 3x + 15
1. Find the HCF for 3x and 15 3
2. HCF goes outside the bracket
3( )
To see what goes inside the bracket
divide each term by HCF
3x ÷ 3 = x
15 ÷ 3 = 5
3( x + 5 )
28-Mar-17
Created by Mr.

8. Factorising Example Factorise 4x2 – 6xy
Check by multiplying out the bracket to get back to where you started
Factorising S3
Credit
Example
Factorise 4x2 – 6xy
1. Find the HCF for 4x2 and 6xy 2x
2. HCF goes outside the bracket
2x( )
To see what goes inside the bracket
divide each term by HCF
4x2 ÷ 2x =2x
6xy ÷ 2x = 3y
2x( 2x- 3y )
28-Mar-17
Created by Mr.

9. Created by Mr. Lafferty@mathsrevision.com
Factorising S3
Credit
Factorise the following :
3(x + 2)
(a) 3x + 6
4xy – 2x
6a + 7a2
(d) y2 - y
Be careful !
2x(2y – 1)
a(6 + 7a)
y(y – 1)
28-Mar-17
Created by Mr.