Answer
$\sqrt[3] (7x+2)^{2}$
Work Step by Step
We know that $a^{\frac{m}{n}}=\sqrt[n] (a^{m})$ (where m and n are positive integers greater than 1 with $\frac{m}{n}$ in simplest form and $\sqrt[n] a$ is a real number).
Therefore, $(7x+2)^{\frac{2}{3}}=\sqrt[3] (7x+2)^{2}$.
