If 4x2 + 3y2 = 28, xy = 4 (x, y > 0) find 7x3 + y2 + 3.

60 62 61 63

63

By Putting x = 2 and y = 2 These values are satisfying the equations: ⇒ 4x2 + 3y2 = 28 ⇒ 4(2)2 + 3(2)2 = 28 ⇒ 28 = 28 Put these values and find: ⇒ 7x3 + y2 + 3. = 7(2)3 + (2)2 + 3= 56 + 4 + 3 = 63