Question 505491
x^3-3x^2-4x+12=0


(x^3-3x^2)+(-4x+12)=0


x^2(x-3)+(-4x+12)=0


x^2(x-3)-4(x-3)=0


(x^2-4)(x-3)=0


(x-2)(x+2)(x-3)=0


x-2 = 0, x+2 = 0, or x-3 = 0


x = 2, x = -2, or x = 3