[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{80x^4}{y^3}\times \cfrac{xy}{5x^2}\implies \cfrac{80x^4xy}{y^35x^2}\implies \cfrac{80x^4xx^{-2}}{5y^3y^{-1}}\implies \cfrac{80x^4x^1x^{-2}}{5y^3y^{-1}}
\\\\\\
\cfrac{16x^{4+1-2}}{y^{3-1}}\implies \cfrac{16x^3}{y^2}[/tex]
