Answer
-2
Work Step by Step
We are given that the slope $m$ of the line passing through the distinct points $(x_{1},y_{1})$ and $(x_{2},y_{2})$ is defined as:
$m=\frac{rise}{run}=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$ (where $x_{2}\ne x_{1}$)
Therefore, $m=\frac{-6-0}{0-(-3)}=\frac{-6}{0+3}=\frac{-6}{3}=-2$.