## Algebra and Trigonometry 10th Edition

$x \leq -1, x \geq 3$
$x^2-2x-3\geq 0$ $(x-3)(x+1) \geq 0$ $x \leq -1, x \geq 3$ (The key numbers are 3 and -1. The interval before -1 and the interval after 3 satisfy the inequality, which can be seen by checking for x=-3 and x=5)