Answer
$\displaystyle \frac{9}{28}$
Work Step by Step
Dividing with $\displaystyle \frac{P}{Q}$ equals multiplying with the reciprocal, $\displaystyle \frac{Q}{P}.$
$\displaystyle \frac{x+5}{7}\div\frac{4x+20}{9}=\frac{x+5}{7}\cdot\frac{9}{4x+20}\qquad$... factor what you can
$=\displaystyle \frac{x+5}{7}\cdot\frac{9}{4(x+5)}\qquad$... divide out the common factors
$=\displaystyle \frac{1}{7}\cdot\frac{9}{4(1)}\qquad$
= $\displaystyle \frac{9}{28}$
