[tex]\bf \left.\qquad \qquad \right.\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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%(-3)^-5 =1/x,
(-3)^{-5}=\cfrac{1}{x}\implies \cfrac{1}{(-3)^5}=\cfrac{1}{x}\implies 1\cdot x=(-3)^5\cdot 1\implies x=(-3)^5
\\\\\\
x=(-3)(-3)(-3)(-3)(-3)\implies x=-243[/tex]