How do you solve x^2(a^2+2ab+b^2) = x(a+b) by factoring?

1 Answer
Aug 21, 2015

x = 0" " or " "x = 1/(a+b)

Explanation:

First, notice that you can write

(a^2 + 2ab + b^2)

as the square of (a + b)

a^2 + 2ab + b^2 = (a + b)^2

Your equation can now be written as

x^2 * (a+b)^2 = x * (a + b)

You can simplify this equation by dividing both sides by (a+b)

(x^2 * (a + b)^color(red)(cancel(color(black)(2))))/color(red)(cancel(color(black)((a+b)))) = (x * color(red)(cancel(color(black)((a+b)))))/color(red)(cancel(color(black)((a+b))))

x^2 * (a + b) = x

Move all the terms to one side of the equation to get

(a+b) * x^2 - x = 0

x * [(a+b)x - 1] = 0

This equation will have two solutions, x = color(green)(0) and

(a+b)x - 1= 0 implies x = color(green)(1/(a+b))