# Math Help - factoring basic college algebra problem

1. ## factoring basic college algebra problem

cant figure this one out. just need to factor it
8r^3 - 27

ive got to

(2r)^3 - 3^3

2. Originally Posted by siberianfog
cant figure this one out. just need to factor it
8r^3 - 27

ive got to

(2r)^3 - 3^3
the factoring format for the difference (and sum) of two cubes should be in your text ...

$a^3 - b^3 = (a-b)(a^2+ab+b^2)$