## Intermediate Algebra (6th Edition)

$\frac{7x}{y^{4}}$
We are given the expression $7xy^{-4}$. $7\times x\times y^{-4}=7\times x\times\frac{1}{y^{4}}=\frac{7x}{y^{4}}$ In general, $x^{−b}=\frac{1}{x^{b}}$, for some number x.