To find the midpoint, add the two X values together and divide that by 2 and then add the two Y values together and divide by 2.
X = 8 +3 = 11 /2 = 5.5
Y = 5 +7 = 12 /2 = 6
Depending on how you need to answer the midpoint for X could stay the fraction 11/2, or you can divide it and get 5.5
The midpoint is (11/2,6) or (5.5,6)