# How do you evaluate x^2+9x-36 with x=-13?

Jan 5, 2017

$16$

#### Explanation:

To evaluate the expression, substitute x = - 13 in for x.

$\Rightarrow {x}^{2} + 9 x - 36$

$= {\left(\textcolor{red}{- 13}\right)}^{2} + \left(9 \times \textcolor{red}{- 13}\right) - 36$

$= 169 - 117 - 36 = 16$