Factor the expression - 8x^{2}z - 16x^{3}. Check your answer.

We could write this expression as 8x^{2}(- z - 2x). However, it is kind of messy to have negative signs in front of every term in the parentheses, and we at Shmoop are a bunch of neat freaks. Let's pull the negative sign (factor of - 1) out: - 8x^{2}(z + 2x). To check the answer, we multiply out: - 8x^{2}(z + 2x) = - 8x^{2}z - 16x^{3}. Awesome. That's totally what we were hoping we would get.