## Precalculus: Mathematics for Calculus, 7th Edition

a. $\mid$$\mid-6\mid-\mid4\mid$$\mid$ $\mid$-6$\mid$ = -(-6) = 6 $\mid$4$\mid$ = 4 $\mid$6-4$\mid$ = $\mid$2$\mid$ = 2 b. $\frac{-1}{\mid-1\mid}$ $\mid$-1$\mid$ = -(-1) = 1 $\frac{-1}{1}$ = -1