Answer
$\{-6\}$
Work Step by Step
Subtract $18$ from both sides.
$3x+18-18=0-18$
Simplify.
$3x=-18$
Divide both sides by $3$.
$\dfrac{3x}{3}=-\dfrac{18}{3}$
Simplify.
$x=-6$
Hence, the solution to the equation is $\{-6\}$.