The question is 15x^3-25x^2+10. I got up to the part of 5x(3x^2-5x+2) but after that I just get stuck.

15x^3-25x^2+10

So you are going to pull out a 5 from all the terms

Like so:

5(3x^3-5x^2+2)

then you are done because you nothing else to pull out or factor out