Factorise: 54x² – 96y²

We have 54x² – 96y² = 6[9x² - 16y²]

                             = 6[(3x)² - (4y)²]

                             = 6 [(3x + 4y)(3x - 4y)]  [Using a² - b² = (a + b)(a - b)]

Thus,    54x² - 96y² = 6 (3x + 4y)(3x - 4y)