Answer
$$(5,-1.5)$$
Work Step by Step
The coordinates $(x_{m},y_{m})$ of the midpoint of the segment joining the points $(x_{1},y_{1})$ and $(x_{2},y_{2})$ are given by
$$x_{m}=\frac{x_{1}+x_{2}}{2}$$ and $$y_{m}=\frac{y_{1}+y_{2}}{2}.$$
Substitute $x_{1}=3$, $y_{1}=3$, $x_{2}=7$ and $y_{2}=-6:$
$$x_{m}=\frac{3+7}{2}=5$$ and $$y_{m}=\frac{3+(-6)}{2}=-1.5.$$
