# How do you factor by grouping 4+9xy-18y-2x?

May 30, 2018

$\left(x - 2\right) \left(9 y - 2\right)$

#### Explanation:

$4 + 9 x y - 18 y - 2 x$

group the terms like this:

$9 x y - 18 y - 2 x + 4$

now factor $9 y$ out of the first 2 terms:

$9 y \left(x - 2\right) - 2 x + 4$

then factor $- 2$ out of the other 2 terms:

$9 y \left(x - 2\right) - 2 \left(x - 2\right)$

Finally factor out the $\left(x - 2\right)$ like this:

$\left(x - 2\right) \left(9 y - 2\right)$