The given points are (-10, -9), and (1,7).
We have to find the midpoint, we'll use the following formula
[tex]M=(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})[/tex]We replace the given points
[tex]\begin{gathered} M=(\frac{-10+1}{2},\frac{-9+7}{2}) \\ M=(\frac{-9}{2},\frac{-2}{2}) \\ M=(-\frac{9}{2},-1) \end{gathered}[/tex]