Answer
Quotient Rule
Work Step by Step
Using the Quotient Rule of radicals which is given by $\sqrt[n]{\dfrac{x}{y}}=\dfrac{\sqrt[n]{x}}{\sqrt[n]{y}}{},$ the expression, $
\dfrac{\sqrt{50a^3}}{\sqrt{2a}}
,$ is equivalent to
\begin{array}{l}\require{cancel}
\sqrt{\dfrac{50a^3}{2a}}
.\end{array}
Hence, the given equality is justified by the $\text{
Quotient Rule
.}$