[tex]\bf ~~~~~~~~~~~~\textit{negative exponents}\\\\
a^{-n} \implies \cfrac{1}{a^n}
\qquad \qquad
\cfrac{1}{a^n}\implies a^{-n}
\qquad \qquad
a^n\implies \cfrac{1}{a^{-n}}\\\\
-------------------------------\\\\
\cfrac{9^2}{9^7}\implies \cfrac{1}{9^{-2}9^7}\implies \cfrac{1}{9^{-2+7}}\implies \cfrac{1}{9^5}\implies \cfrac{1}{59049}[/tex]
