Question

Factorise the expression: q

2

– 10q + 21
​

Answer 1

Answer:

$q^2- 10q + 21 = 0 \\ \\ = > q^2- ( 7 + 3 ) q + 21= 0 \\ \\ = > q^2 - 7q - 3q + 21 = 0 \\ \\ = > q ( q - 7 ) - 3 ( q - 7 ) = 0 \\ \\ => ( q - 7 ) ( q - 3 ) = 0$

either

q - 7 =0

=> q = 7

oR

q - 3 = 0

=> q = 3

hope it helps uH :)

Answer 2

Answer:

-(10×2)+21

-20+21

1 ANS