Exercise 51 Page 65

We want to verify if any values contained in the replacement set are solutions of this equation. We will replace the variable with each value from the set and check if the equation is true for any of them.

$x$	$14+x=21$	Simplify	True or False?
$1$	$14+1\stackrel{?}{=}21$	$15\ne 21$	False
$3$	$14+3\stackrel{?}{=}21$	$17\ne 21$	False
$5$	$14+5\stackrel{?}{=}21$	$19\ne 21$	False
$7$	$14+7\stackrel{?}{=}21$	$21=21$	True
$9$	$14+9\stackrel{?}{=}21$	$23\ne 21$	False

Since the equation is true when $x=7,$ the solution set is $\{7\}.$