Question

PLEASE HELPP! Question 1: Factorise each of the following (a) x² + 7x + 12 (b) x² + 6x + 8 (c) x² + 5x + 6 (d) x² + 8x + 7

Answer 1

a) the middle number is seven and the last number is 12

factorising means we want something like (x + ___) (x +__)

Which number go into the blanks?

we need 2 numbers that add together to get 7 multiplied together to get 12.

3 + 4 is equal to 7

3x4=12

Answer:

(x+3)(x+4)

b) the middle number is 6 and the last number is 8

Factoring means we want something like

(x+___)(x+___)

which number go to the blanks?

We need two numbers that add together to get 6 and multiply together to get 8

2+4=6

2x4=8

Answer:

(x+2)(x+4)

c) the middle number is 5 and the last number is 6

we need two numbers that add together to get 5 and multiply together to get 6

2 + 3 is 5 and 2 x 3=6

Answer:

(x+2)(x+3)

Answer:

d) (x+1)(x+7)

Answer 2

Using the mid-term break formula for all of them.

a) x²+7x+12

= x²+3x+4x+12

= x(x+3)+4(x+3)

= (x+4)(x+3)

b) x²+6x+8

= x²+2x+4x+8

= x(x+2)+4(x+2)

= (x+4)(x+2)

c) x²+5x+6

= x²+2x+3x+6

= x(x+2)+3(x+2)

= (x=3)(x+2)

d) x²+8x+7

= x²+7x+x+7

= x(x+7)+1(x+7)

= (x+1)(x+7)