# Stumped

• September 9th 2008, 04:16 PM
4kVoX
Stumped
So I skipped over this question after 10 minutes of frustration.
Help would be really appreciated =).

Factor:
X^2 - 20

thanks.
• September 9th 2008, 04:38 PM
mr fantastic
Quote:

Originally Posted by 4kVoX
So I skipped over this question after 10 minutes of frustration.
Help would be really appreciated =).

Factor:
X^2 - 20

thanks.

Two things:

1. $x^2 - 20 = x^2 - (\sqrt{20})^2$.

2. $A^2 - B^2 = (A - B)(A + B)$.