## Algebra: A Combined Approach (4th Edition)

$-\frac{1}{64}$
Step 1: $-256^{-\frac{3}{4}}$ Step 2: $\frac{1}{(-256)^{\frac{3}{4}}}$ Step 3: Since $4^{4}=256$, the expression becomes $\frac{1}{(-4^{4})^{\frac{3}{4}}}$ Step 4: Simplifying the indexes, the expression becomes $\frac{1}{(-4)^{3}}$ Step 5: This can be simplified as $\frac{1}{-64}$ or $-\frac{1}{64}$