x^3 + 3x^2 - 9x - 27 = 0
looks like grouping will work
x^2(x+3) - 9(x+3) = 0
(x+3)(x^2 - 9) = 0
(x+3)(x+3)(x-3) = 0
x = ± 3
(x = -3 is a double root)
how to you solve polynomial equation by factoring
x^3 + 3x^2 - 9x = 27
1 answer