I have a problem with derivatives, I've been trying to solve but I was not able to do it.

> 
> A parabola is tangent to the line $3x-y+6 = 0$ in the point $(0,6)$
>  and goes through the point $(1,0)$. Find the equation of the parabola
>  supposing the equation is of the form $y = Ax^2 +Bx +C$ where $A B C$
>  are unknown.
> 
> 
> 

I would like you to help me to solve it. So far I know $(1,0)$ is the vertex of the parabola and that $(0,6)$ is a point of the parabola,thus the directive
is $x=0$

Any help would be appreciated.