The midpoint of the line segment PQ is (-1, -3).
Midpoint formula:
[tex] \frac{x_{1}+ x_{2} }{2} [/tex] , [tex] \frac{ y_{1} + y_{2} }{2} [/tex]
[tex] \frac{-7+5}{2} [/tex] , [tex] \frac{3+(-9)}{2} [/tex]
[tex] \frac{-2}{2} [/tex] , [tex] \frac{-6}{2} [/tex]
(-1, -3)