Question 1039378
<pre>
The equation of a parabola is

4p(y-k) = (x-h)^2

Where 

(h,k) is the vertex which is halfway between
the directrix and the focus.

|p| is the distance from the focus to the vertex,
and also from the vertex to the directrix. 

p is taken as a positive number if the parabola opens
upward, i.e., the directrix is below the vertex and focus.

p is taken as a negative number if the parabola opens
downward, i.e., the directrix is above the vertex and focus.  

You can find those and substitute in

4p(y-k) = (x-h)^2

Edwin</pre>