How do I find the domain? Could someone please assist me through one of these problems? I vaguely remember going over this but I need to review this material...any assistance would be great!
On the denominator, the values $\displaystyle 2,-5$ make this one zero, then you'll get something like $\displaystyle \frac a0$ and that deserves a punishment.
So the domain will be $\displaystyle \text{Dom}\,f=\mathbb R-\{2,-5\}.$