Answer
$x^2-16\gt0$
$(x+4)(x-4)\gt0$
$x\lt-4$ and $x\gt4$
Work Step by Step
Step 1: Factorize quadratic inequality (difference of squares)
Step 2: The roots of the function is $x=-4$ and $x=4$
Step 3: The quadratic function of the inequality is greater than $0$ at $x\lt-4$ and $x\gt4$
