Answer
$y=-\dfrac{6}{5}$
Work Step by Step
Using the properties of equality, the value of the variable that satisfies the given expression, $
12=5y+18
,$ is
\begin{array}{l}\require{cancel}
-5y=18-12
\\\\
-5y=6
\\\\
y=\dfrac{6}{-5}
\\\\
y=-\dfrac{6}{5}
.\end{array}