Homework Ex 6i No.s 1,5,8,10,13,16,24,30

35a b 2 – 10b 9(3c + 2) 3d(5d + 4) 12e 2 f – 8ef 2 5gh(7g – 5h)

To be able to factorise we must ask 1. What’s common amongst the terms? Put what’s common outside the brackets 2. What’s left after taking out the common? We put what’s left inside the brackets Let’s look at an example!

How can we write 10a 2 as a product of factors? 10a 2 = 2 x 5 x a x a How can we write 15a as a product of factors? 15a = 3 x 5 x a What’s common? 5a What’s left? 2a + 3 Factorised answer: 5a(2a + 3)

How can we write 18b 2 as a product of factors? 18b 2 = 2 x 3 x 3 x b x b How can we write 12b as a product of factors? 12b = 2 x 3 x 2 x b What’s common? 6b What’s left? 3b - 2 Factorised answer: 6b(3b - 2)

How can we write 21ab 2 as a product of factors? 21ab 2 = 7 x 3 x a x b x b How can we write 28a 2 b as a product of factors? 28a 2 b = 2 x 2 x 7 x a x a x b What’s common? 7ab What’s left? 3b – 4a Factorised answer: 7ab(3b – 4a)

Extension: Let’s Practise  Choose 5 from each exercise to do!

Answers to Activity 1

Homework Pg 142 – Pg 143 Exercise 7a 2,8 11,17 20,26 33,36