The midpoint, if the endpoints are (x₁,y₁) and (x₂,y₂):
\((\frac{x_1+x_2}{2}, \frac{y_1+y_2}{2})\)
\((9,8) \\
x_1=9 \\ y_1=8 \\ \\
(-1,-2) \\
x_2=-1 \\ y_2=-2 \\ \\
\frac{x_1+x_2}{2}=\frac{9-1}{2}=\frac{8}{2}=4 \\
\frac{y_1+y_2}{2}=\frac{8-2}{2}=\frac{6}{2}=3\)
The midpoint of AB is (4,3).
