Answer :
[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}}
\\\\
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\cfrac{\quad \frac{15x^5}{24y^8}\quad }{\frac{4x^2}{8y^4}}\implies \cfrac{15x^5}{24y^8}\cdot \cfrac{8y^4}{4x^2}\implies \cfrac{120x^5y^4}{96y^8x^2}\implies \cfrac{120}{96}\cdot \cfrac{x^5x^{-2}}{y^8y^{-4}}
\\\\\\
\cfrac{5}{4}\cdot \cfrac{x^{5-2}}{y^{8-4}}\implies \cfrac{5x^3}{4y^4}[/tex]