Question 948701
Use the definition of a parabola and the Distance Formula directly.  You need to know the focus of the parabola.  The focus is on the opposite side of the vertex than the directrix.  This will put the focus at (0,-8).


Distance from points (x,y) to (0,-8) equals distance from points (x,y) to (x,8).


Can you transcribe that into an equation using the Distance Formula, and simplify the equation?


Note also that you <i>should</i> draw a picture of this.