# How do you factor  3x^2 z – 3zx – 18z?

Apr 25, 2018

$3 z \left(x + 1\right) \left(x - 3\right)$

#### Explanation:

first, we can see that $3 z$ is a common factor in all three terms. isolate that out and factor the rest.

$3 {x}^{2} z - 3 z x - 18 z$

$3 z \left({x}^{2} - x - 6\right)$

$3 z \left(x + 1\right) \left(x - 3\right)$

Apr 25, 2018

$3 z \left(x - 3\right) \left(x + 2\right)$

#### Explanation:

$\text{take out the "color(blue)"common factor } 3 z$

$= 3 z \left({x}^{2} - x - 6\right)$

$\text{the factors of - 6 which sum to - 1 are - 3 and + 2}$

$= 3 z \left(x - 3\right) \left(x + 2\right)$