I'm on my last problem for my lesson and I'm a little stumped and need a push in the right direction.

Problem: "One factor of $\displaystyle 4x^3+15x^2-31x-30$ is x-2. Find the other factors."

I don't want the answer but if someone could explain to me how they even got x-2 as a factor I should be able to figure the rest out or if someone knows of a lesson that explains this that would be helpful as well.

Thanks for looking!