# How do you factor by grouping 3x^2 - 2x - 15x + 10?

May 22, 2015

$3 {x}^{2} - 2 x - 15 x + 10$

We can make groups of two to factorise this expression:
$\left(3 {x}^{2} - 15 x\right) + \left(- 2 x + 10\right)$

$3 x$ is common to both the terms in the first group, and $- 2$ is common to both the terms in the second group

We can write the expression as :
$3 x \left(x - 5\right) - 2 \left(x - 5\right)$
=color(green)((3x - 2)(x - 5) , is the factorised form.