Question

Factorise completely
$1) {x}^{2} - 12x - 13$
$2){32y}^{2} + 8y$
$3) {x}^{2} - 9$

Answer 1

1. Number that adds up to -12 and multiplied by the same # that gives u -13. Set it up like this because both are negative so, u need 1 negative and 1 positive.
(x-13)(x+1)

2. Same rule applies. GCF
8y(4y+1)

3. (x+3)(x-3)