Here, we have a parabola with its focus and directrix. Point P lies on the parabola itself. Mess around with this app by moving any of the BIG POINTS anywhere you'd like.
Other than mentioning the fact that [color=#bf9000][b]P[/b] [/color]always lies on a parabola, how would you describe all possible locations for [b][color=#bf9000]P[/color][/b] above? Be specific.