You can put this solution on YOUR website! You are given enough information to find the directrix. Use the distance formula and definition of a parabola to derive the equation for the specific parabola of your example; and adjust the form of the equation to whichever format you want.
The directrix is on the other side of the vertex than the focus. The directrix is y=9, so the general point for the directrix would be (x,9).
Work with this:
Focus to parabola equals directrix to parabola.