# Thread: Difference of Squares Problem

1. ## Difference of Squares Problem

I was doing a problem on practicem 4x^2 - 361. I know how to use the quadratic formula but is it impossible to factor difference by squares when the second number is a prime number. can you factor using a fraction or something?

2. ## Re: Difference of Squares Problem

Originally Posted by kingcobrasnake
I was doing a problem on practicem 4x^2 - 361. I know how to use the quadratic formula but is it impossible to factor difference by squares when the second number is a prime number. can you factor using a fraction or something?
$4x^2-361=(2x-\sqrt{361})(2x+\sqrt{361})$

3. ## Re: Difference of Squares Problem

oh woah, that makes so much more sense. idk how i didnt think of that

thx