Answer
$\color{blue}{\dfrac{1}{x^{10/3}}}$
Work Step by Step
RECALL:
(1) $a^m \cdot a^n = a^{m+n}$
(2) $\dfrac{a^m}{a^n} = a^{m-n}$
(3) $a^{1/n} = \sqrt[n]{a}$
(4) When $n$ is odd, $\sqrt[n]{a^n}=a$
(5) $a^{m/n} = \left(\sqrt[n]{a}\right)^m$
(6) $(ab)^m=a^mb^m$
(7) $(a^m)^n=a^{mn}$
(8) $a^{-m}=\dfrac{1}{a^m}$
Use rule (7) above to obtain:
$=\dfrac{x^{(2/3) \cdot 2}}{x^{2 \cdot (7/3)}}
\\=\dfrac{x^{4/3}}{x^{14/3}}$
Use rule (2) above to obtain:
$=x^{4/3-14/3}
\\=x^{-10/3}$
Use rule (8) above to obtain:
$=\color{blue}{\dfrac{1}{x^{10/3}}}$
