Midpoint Formula: M = (x₁ + x₂)/2 , (y₁ + y₂)/2
Consider (4, -7) the first point and (-1, 7) the second point, then
M = [tex](\frac{4 +(-1)}{2} , \frac{-7 + 7}{2} )[/tex]
= [tex](\frac{3}{2} , \frac{0}{2} )[/tex]
= (1.5, 0)