Answer
$x=5$
Work Step by Step
Since $y=b^x$ is equivalent to $\log_b y=x,$ then the given equation, $
\log_x \sqrt[3]{5}=\dfrac{1}{3}
,$ is equivalent to
\begin{array}{l}\require{cancel}
x^{\frac{1}{3}}=\sqrt[3]{5}
\\\\
x^{\frac{1}{3}}=5^{\frac{1}{3}}
.\end{array}
Since the exponents are the same, then the bases can be equated. Hence,
\begin{array}{l}\require{cancel}
x=5
.\end{array}