Answer
$3\frac{3}{4}$
Work Step by Step
$\frac{x}{y+z}=\frac{\frac{1}{2}}{-\frac{2}{3}+\frac{4}{5}}=\frac{\frac{1}{2}}{-\frac{2\times5}{3\times5}+\frac{4\times3}{5\times3}}=\frac{\frac{1}{2}}{-\frac{10}{15}+\frac{12}{15}}=\frac{\frac{1}{2}}{\frac{2}{15}}=\frac{1}{2}\div\frac{2}{15}=\frac{1}{2}\times\frac{15}{2}=\frac{15}{4}=3\frac{3}{4}$
