Let $ABC$ be a triangle having respectively orthocentre and circumcentre at $(9,5)$ and $(0,0)$. If the equation of side $BC$ is $2x-y=10$, then find the possible co-ordinates of vertex $A$.  

**MY ATTEMPT:**
I found the equation of the perpendicular on $BC$ passing through $H$. So, $A$ is a point on this line. But, then what must I do next. Please help.