Question

Factor z2 + 17z + 72.

Answer 1

Hello!

It looks like you meant,
$z^2+17z+72$
Break the expression into two groups, that would imply splitting the 17.
$=\left(z^2+8z\right)+\left(9z+72\right)$
Let's start factoring.
First, factor the $z$ from $z^2+8z$
Then, factor the $9$ from $9z+72$
We would be left with,
$=z\left(z+8\right)+9\left(z+8\right)$
Factor out the common term, which is $(z+8)$
$=\left(z+8\right)\left(z+9\right)$

Our final answer would be,
$=\left(z+8\right)\left(z+9\right)$

You can feel free to let me know if you have any questions regarding this!
Thanks!

- TetraFish