## Precalculus (6th Edition) Blitzer

$\frac{y^{2}}{25x^{6}}$
Start with the given expression: $(\frac{5x^{3}}{y})^{-2}$ Use negative exponent rule to invert fraction: $(\frac{y}{5x^{3}})^{2}$ Remove the parentheses: $\frac{y^{2}}{5^{2}(x^{3})^{2}}$ Use power rule to simplify denominator: $\frac{y^{2}}{25x^{6}}$