The solution is,

The analytical formula of parabola is y =-x-4;

(2) Point (x, 0) where point P moves, BP2 = BD? BC,

Let x = 0 and y = -4,

C(0, -4) of the point coordinates.

∫PD∑AC，

∴△BPD∽△BAC，

∴。

BC =，

AB = 6，BP = X-(-2)= x +2 .

∴ BD = =. About

∫BP2 = 400 BC

∴(x +2)2 =

Solution, X 1 = X2 = -2(-2 meaning of unqualified question, rounded)

∴ The coordinate of point P is (0), that is, when point P (0) moves, BP2 = BD? BC;

(3) BPD∽△BAC，

Yes

∴×

Bpc of sδ = x (x+2) * 4-

When x = 1, the maximum value of S△BPC is 3. about

That is, the coordinates of point P (1, 0) and the delta △PDC area.