Hi Tina,

The final quiz actually has some problems from the previous chapters in it. This question, is actually 7.20, which references 7.19. I would recommend you take a look at the Chapter 7 practice quiz again and look at 7.19 and 7.20 there for the trick of factoring the solution mentions.

That being said, this question does amount to (after combining like terms and getting rid of the negatives) solving $x^3 + 3x^2 + x + 3 = 0$. Our hope when solving a general cubic is that we can find one rational root to help the factoring. The Rational Root Theorem can help. For this cubic, remember this theorem says that the only possible rational roots are $\pm 1$ and $\pm 3$. Trial and error here gives us that $x = -3$ is a root. Then factoring or polynomial long division gives us$$x^3 + 3x^2 + x + 3 = (x+3)(x^2+1)$$so $x=-3$ is the only real root.