Question

How do you factor the expression 5x² - 45?

Answer 1

`5(x-3)(x+3)`

Explanation:

Given: `5x^2-45`.

Factor `5` out.

`=5(x^2-9)`

`=5(x^2-3^2)`

Now use the difference of squares, `(a^2-b^2)=(a+b)(a-b)`.

`=5(x-3)(x+3)`