Chapter 4 Quadratic Functions and Factoring - 4.8 Use the Quadratic Formula and the Discriminant - 4.8 Exercises - Skill Practice - Page 296: 30

$$n=9,\:n=-2$$

Solving the equation using the quadratic formula, we find: $$n_{1,\:2}=\frac{-\left(-63\right)\pm \sqrt{\left(-63\right)^2-4\cdot \:9\left(-162\right)}}{2\cdot \:9} \\ n=9,\:n=-2$$ Checking by factoring the expression, we find: $$9\left(n^2-7n-18\right)\\ 9\left(n+2\right)\left(n-9\right)$$