Question

How to factorise 5x square -20?

Answer 1

5(x² - 4)

Explanation:

5x² - 20

5 can divide both 5 and 20, 5x²/5 and -20/5 = x² and -4

5(x² - 4), to know if you are correct, multiply 5 by the bracket and you get the question back