Answer:
(9/2, -25/2)
Step-by-step explanation:
The Midpoint Formula: The midpoint of the segment joining points [tex](x_1,\,y_1)[/tex] and [tex](x_2,\,y_2)[/tex] is [tex]\left(\frac{x_1+x_2}{2},\,\frac{y_1+y_2}{2}\right)[/tex].
[tex]\left(\frac{20+(-11)}{2},\,\frac{-15+(-10)}{2}\right)[/tex]
[tex](\frac{9}{2},\,-\frac{25}{2})[/tex]
By the way, instead of trying to memorize the formula, why not just think the x-coordinate of the midpoint is the average of the x-coordinates of the points. The y-coordinate of the midpoint is the average of the y-coordinates of the points.
The average of two numbers is exactly halfway between them!
