
$\begin{aligned}
& \therefore \quad \text { Equation of parabola is } P S=(1) P M \
& \Rightarrow P S^2=P M^2 \
& (x-3)^2+(y-6)^2=\left(\frac{x+2 y}{\sqrt{5}}\right)^2 \
& 5 x^2-30 x+5 y^2-60 y+225=x^2+4 y^2+4 x y \
& 4 x^2+y^2-4 x y-30 x-60 y+225=0
\end{aligned}Weget:\alpha=4, \beta=1, \gamma=4\therefore \alpha+\beta+\gamma=9$