Put the equation into vertex form. Since the variable is squared, this is a parabola with a horizontal axis of symmetry and a vertical directrix. Vertex form for such a parabola is the equation solved for in terms of everything else.
Rewrite so that the elements of the vertex form are evident:
The general form of a parabola with a horizontal axis is:
Which is a parabola with a horizontal axis,
vertex at ,
parameter ,
directrix equation: ,
focus at ,
and latus rectum endpoints at .
I'll help you find the parameter :
The rest is just plugging in numbers.
John
My calculator said it, I believe it, that settles it
