Question

Factorise x^2-9
`x^(2) -9`

Answer 1

(x - 3)(x + 3)

Explanation:

x² - 9 ← is a difference of squares and factors in general as

a² - b² = (a - b)(a + b) , then

x² - 9

= x² - 3²

= (x - 3)(x + 3)