If a2 + b2 = 65 and ab = 8, a > b > 0, then find the value of a2 - b2.

72 60 65 63

63

a2 + b2 = 65 ab = 8 Put a = 8 and b = 1 a2 - b2 = 82 - 12           = 64 - 1 = 63