How do you factor completely x^2+2ax = b^2-a^2x2+2ax=b2a2?

1 Answer
Mar 21, 2018

In factored form this is:

(x+a-b)(x+a+b) = 0(x+ab)(x+a+b)=0

Explanation:

The difference of squares identity can be written:

A^2-B^2 = (A-B)(A+B)A2B2=(AB)(A+B)

We will use this with A=(x+a)A=(x+a) and B=bB=b.

Given:

x^2+2ax = b^2-a^2x2+2ax=b2a2

Add a^2-b^2a2b2 to both sides to get:

0 = x^2+2ax+a^2-b^20=x2+2ax+a2b2

color(white)(0) = (x+a)^2-b^20=(x+a)2b2

color(white)(0) = ((x+a)-b)((x+a)+b)0=((x+a)b)((x+a)+b)

color(white)(0) = (x+a-b)(x+a+b)0=(x+ab)(x+a+b)