Hello! Remember you have to write complete questions in order to get good and exact answers. Suppose that you have a segment defined by the endpoints:
[tex]a(3,1) \ and \ b(5,9)[/tex]
[tex]The \ midpoint \ formula \ of \ the \ line \ segment \\ that \ joins \ the \ two \ points \ (x_{1},y_{1}) \ and \ (x_{2},y_{2}) \ is \\ given \ by \ the \ following \ Midpoint \ Formula:\\ \\ Midpoint=(\frac{x_{1}+x_{2}}{2},\frac{y_{1}+y_{2}}{2})[/tex]
So:
[tex]x_{1}=3, \ y_{1}=1 \\ \\ x_{2}=5, y_{2}=9 \\ \\ \\ M:Midpoint \\ \\ \\ M=(\frac{3+5}{2},\frac{1+9}{2}) \\ \\ M=(\frac{8}{2},\frac{10}{2}) \\ \\ \boxed{M=(4,5)}[/tex]