Answer
$\color{blue}{\left\{-1, 5\right\}}$
Work Step by Step
RECALL:
$|x|=a \longrightarrow x=a \text{ or } x = -a$
Use the rule above to have:
$|2-x|= 3 \longrightarrow 2-x=3 \text{ or } 2-x = -3$
Solve each equation to obtain:
$2-x=3
\\-x=3-2
\\-x=1
\\x=-1$
or
$2-x=-3
\\-x=-3-2
\\-x=-5
\\x=5$
Thus, the solution set is $\color{blue}{\left\{-1, 5\right\}}$.