Basic College Mathematics (10th Edition)

$-1\frac{5}{8}$
We have $$-m-3n$$ Where $m = \frac{1}{2}$, $n=\frac{3}{8}$ Then if you substitute each letter by her value $$-\frac{1}{2} - 3*\frac{3}{8} = -\frac{1}{2} - \frac{9}{8} = \frac{-4-9}{8} = \frac{-13}{8} = -1\frac{5}{8}$$