Chapter 4 Quadratic Functions and Factoring - 4.8 Use the Quadratic Formula and the Discriminant - 4.8 Exercises - Skill Practice - Page 296: 24

$$m=9,\:m=-11$$

Solving the equation using the quadratic formula, we find: $$m_{1,\:2}=\frac{-2\pm \sqrt{2^2-4\cdot \:1\left(-99\right)}}{2\cdot \:1} \\ m=9,\:m=-11$$ Checking by factoring the expression, we find: $$m\left(m-9\right)+11\left(m-9\right) \\ \left(m-9\right)\left(m+11\right)$$