Answer
$3\frac{3}{5}$
Work Step by Step
When $x=\frac{3}{4}$ and $y=-\frac{4}{7}$
$\frac{\frac{9}{14}}{x+y}$
$=\frac{9}{14}\div(x+y)$
$=\frac{9}{14}\div[(\frac{3}{4}+(-\frac{4}{7})]$
$=\frac{9}{14}\div(\frac{3}{4}-\frac{4}{7})$
$=\frac{9}{14}\div(\frac{21}{28}-\frac{16}{28})$
$=\frac{9}{14}\div\frac{5}{28}$
$=\frac{9}{14}\times\frac{28}{5}$
$=\frac{9}{1}\times\frac{2}{5}$
$=\frac{18}{5}$
$=3\frac{3}{5}$
