Question

Factor the polynomial completely

Answer 1

3x(y - 4)(y + 4)

3xy² - 48x ( take out the common factor 3x )

= 3x( y² - 16 )

y² - 16 is a difference of squares, which factors in general as

a² - b² = (a - b)(a + b)

here a = y and b = 4

y² - 16 = (y - 4)(y + 4), hence

3xy² - 48x = 3x(y - 4)(y + 4)