$$\frac { 3 \sqrt { 3 } } { \sqrt { 3 } - \sqrt { 2 } } = a + \sqrt { b }$$
$b=\left(-a+3\sqrt{6}+9\right)^{2}$
$-a+3\sqrt{6}+9\geq 0$
$a=-\sqrt{b}+3\sqrt{6}+9$
$b=\left(-a+3\sqrt{6}+9\right)^{2}$
$a=3\sqrt{6}+9\text{ or }arg(-a+3\sqrt{6}+9)<\pi $
$a=-\sqrt{b}+3\sqrt{6}+9$
$b\geq 0$