x³ + 9x² - 4x - 36 = (x³ + 9x²) - (4x + 36) = x²(x + 9) - 4(x + 9) =
= (x + 9)(x² - 4) = (x + 9)(x - 2)(x + 2)
x³ + 9x² - 4x - 36 = (x³ + 9x²) - (4x + 36) = x²(x + 9) - 4(x + 9) =
= (x + 9)(x² - 4) = (x + 9)(x - 2)(x + 2)