Given data:
The coordinate of first point is (a,b)=(-1,5).
The coordinate of the second point is (c,d)=(5,5).
The expression for mmid point is,
x=(a+c)/2
y=(b+d)/2
Substitute the given values in the above expression.
x=(-1+5)/2
=2/1
y=(5+5)/2
=5/1
Thus, the coordinate of the midpoint is (2/1, 5/1).