If (4x - 7y) = 11 and xy = 8. what is the value of 16x2 + 49y2, given that x and y are positive numbers?

596 484 569 448

569

If (4x - 7y) = 11 xy = 8 Then = 16x2 + 49y2 ( a - b )2 = a2 + b2 - 2ab ( 11 )2 = 16x2 + 49y2 - 2 × 28  × 8  569 = 16x2 + 49y2