To find the midpoints we have to apply the next formula:
Remembering that:
(x,y)
So:
(-2,-2) = (x1,y1)
x1=-2
y1=-2
x2=-4
y2=13
Replacing with the values given:
x =(x1+x2)/2)= (-2+(-4) )/2 = (-2-4)/2 = -6/2 = -3
y= (y1+y2)/2= (-2+13)/2= 11/2 = 5.5
Midpoint: ( -3 , 5.5 )