Question

if 3x-2y=14 and xy=12 find 27x cube - 8y cube

Answer 1

$27 {x}^{3} - 8 {y}^{3} \\ = {(3x)}^{3} - {(2y)}^{3} \\ = {(3x - 2y)}^{3} + 3 \times 3x \times 2y(3x - 2y) \\ = {14}^{3} + 18 \times 12 \times 14 \\ = 5768$
hope it will help you