What is the midpoint of h(7,10),x(5,-8)

See attachment

then we add 7 and 5 and divide that by 2, which gives you 6 (x-coordinate)
and add 10 and -8 and divide that by 2, which gives you 1 (y-coordinate)

the answer is (6, 1)

justification
so midpoint is basically the middle point of 2 points
that's why we have to add the two x coordinates first then divide it by 2
                               or add the two y coordinates then divide it by 2