Answer
$x=-\dfrac{1}{3}$
Work Step by Step
Using the properties of equality, the solution to the given equation, $
7-3x=8
$, is
\begin{array}{l}\require{cancel}
-3x=8-7
\\\\
-3x=1
\\\\
x=\dfrac{1}{-3}
\\\\
x=-\dfrac{1}{3}
.\end{array}