Answer
$\dfrac{x^4y^7}{9}$
Work Step by Step
RECALL:
$a^{-m}=\dfrac{1}{a^{m}}, a\ne0$
Use the rule above to obtain:
$=\dfrac{\frac{1}{3^2}\cdot x^4}{\frac{1}{y^7}}
\\=\dfrac{\frac{1}{9}\cdot x^4}{\frac{1}{y^7}}$
Use the rule $\frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \cdot \frac{d}{c}$ to obtain:
$=\dfrac{1}{9} \cdot x^4 \cdot \dfrac{y^7}{1}
\\=\dfrac{x^4y^7}{9}$
