The function $f(x)=\frac{x}{x^2-6 x-16}, x \in \mathbb{R}-\{-2,8\}$
decreases in $(-\infty,-2) \cup(-2,8) \cup(8, \infty)$
increases in $(-\infty,-2) \cup(-2,8) \cup(8, \infty)$
decreases in $(-2,8)$ and increases in $(-\infty,-2) \cup(8, \infty)$
decreases in $(-\infty,-2)$ and increases in $(8, \infty)$
