If x3 + y3 = 855 x + y = 15 Find the value of xy.

15 45 56 58

56

x3 + y3 = 855 x + y = 15 (x + y)3 = x3 + y3 + 3xy (x + y) 3375 = 855 + 45xy xy = \(\frac{2520}{45}\) xy = 56