If 4x2 + 3y2 = 48 , xy = 6 (x, y > 0) find 3x3 + y2.

85 59 68 84

85

By Putting x = 3 and y = 2 These values are satisfying the equations: ⇒ 4x2 + 3y2 = 48 ⇒ 4(3)2 + 3(2)2 = 48 ⇒ 48 = 48 Put these values and find: ⇒ 3x3 + y2 = 3(3)3 + (2)2= 81 + 4 = 85