Algebra: A Combined Approach (4th Edition)

$(-16)^{-5/4}=\dfrac{1}{(-16)^{5/4}}$
$(-16)^{-5/4}$ To change the sign of the exponent, rewrite this expression as $\dfrac{1}{(-16)^{5/4}}$: $(-16)^{-5/4}=\dfrac{1}{(-16)^{5/4}}$