Question

Find the coordinates of the midpoint of a segment with the endpoints
(16,5) & (28, -13).

Answer 1

You can find the mid-point of any segment given the end points of it with the following expression that represents a mid point "M" for any segment:
\[M(\frac{ x_2+x_1 }{ 2 },\frac{ y_2+y_1 }{ 2 })\]
It's just the sum of the coordinates of the end-points and then you divide them by two.
So, fo the segments with the end-points (16,5) and (28,-13), the mid point "M" will have the following values:
\[M(\frac{ 16+28 }{ 2 },\frac{ 5-13 }{ 2 })\]
I'll leave the duty of calculating those fractions to you.