Answer:
x^3 + 10x^2 + 21x - 12
Step-by-step explanation:
(x + 4)(x^2 + 6x - 3)
you can separate to make it easier for u
x(x^2 + 6x - 3) + 4(x^2 + 6x - 3), this is optional u don't have to do this part
x^3 + 6x^2 - 3x + 4x^2 + 24x - 12
add like terms together
x^3 + 10x^2 + 21x - 12