Answer
$\frac{6+2\sqrt{mn}+15\sqrt m+5m\sqrt n}{9-mn}$.
Work Step by Step
The given expression is
$=\frac{2+5\sqrt {m}}{3-\sqrt{mn}}$
Multiply and divide by the conjugate of the denominator.
$=\frac{2+5\sqrt m}{3-\sqrt{mn}}\cdot \frac{3+\sqrt{mn}}{3+\sqrt{mn}}$
Use the FOIL method.
$=\frac{6+2\sqrt{mn}+15\sqrt m+(5\sqrt m)\cdot (\sqrt{mn}}{9+3\sqrt{mn}-3\sqrt{mn}+(-\sqrt{mn})(\sqrt{mn})}$
Simplify.
$=\frac{6+2\sqrt{mn}+15\sqrt m+5m\sqrt n}{9-mn}$.
