Answer
$|x-8|\gt5$
Work Step by Step
$|u|\lt a~↔~-a\lt u\lt a$
$|u|\leq a~↔~-a\leq u\leq a$
$|u|\gt a~↔~u\lt-a~or~u\gt a$
$|u|\geq a~↔~u\leq-a~or~u\geq a$
The numbers must be greater than 13 or less than 3:
$x\lt3$ or $x\gt13$
$x-8\lt3-8$ or $x-8\gt13-8$
$x-8\lt-5$ or $x-8\gt5$
$|x-8|\gt5$
