Midpoint Definition: The point where a line is perfectly split in half
Coordinates exist in the form of ( x, y )
Generally, you find the midpoint by adding up the two numbers and dividing the sum by 2.
In other words,
Midpoint = ( [tex]\frac{x1+x2}{2} , \frac{y1+y2}{2}[/tex] )
You should get ( -22.5, 11 ) as your answer.