## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$t \le -21 \text{ or } t \ge 21$
$\bf{\text{Solution Outline:}}$ To solve the given inequality, $|t| \ge 21 ,$ use the definition of a greater than (greater than or equal to) absolute value inequality. $\bf{\text{Solution Details:}}$ Since for any $c\gt0$, $|x|\gt c$ implies $x\gt c \text{ or } x\lt-c$ (which is equivalent to $|x|\ge c$ implies $x\ge c \text{ or } x\le-c$), the inequality above is equivalent to \begin{array}{l}\require{cancel} t \ge 21 \\\\\text{OR}\\\\ t \le -21 .\end{array} Hence, the solution set is $t \le -21 \text{ or } t \ge 21 .$