Answer
$(-\infty,-4)\cup(2,\infty)$
Work Step by Step
Step 1. Factor the left side to get $(x+4)(x-2)\gt0$ and we can find the boundary points as $x=-4,2$
Step 2. Using the test points to examine the signs on each interval, we have $...(+)...(-4)...(-)...(2)...(+)...$
Step 3. We can find the solution as $(-\infty,-4)\cup(2,\infty)$
