Answer:
5x^3+15x^2-35x
Explanation:
Firstly, you want to combine the "x"s in the (5x*x^2) and the (5x*3x). Once you have that (you will get 5x^3 and 15x^2), you can move onto the last set of parenthesis. We can get 35x from here. Finally, the last step is to add the correct signs. Our final answer will then be 5x^3+15x^2-35x. I hope this helped and please don't hesitate to reach out with more questions!