Answer
$9^{8}x^{8}$
Work Step by Step
$\displaystyle \frac{(9x)^{10}}{(9x)^{2}}\qquad$...apply The Quotient Rule $\displaystyle \frac{a^{m}}{a^{n}}=a^{m-n}$
$=(9x)^{10-2}$
$=(9x)^{8}\qquad$...raise product to the $8$th power.$(ab)^{n}=a^{n}b^{n}$
$=9^{8}x^{8}$
