Question 913711
the vertex form of a Parabola opening up(a>0) or down(a<0), {{{y=a(x-h)^2 +k}}} 
where(h,k) is the vertex  and  x = h  is the Line of Symmetry
p = {{{1/(4a)}}}, where  the focus is (h,k + p) and the Directrix y = (k - p)

1. {{{y = x^2}}}, V(0,0)  a = 1,  p = 1/(4a) , p = 1/4, F(0,.25) directrix y = -.25 
2. {{{y = cx^2}}}, V(0,0) a = c,  p = 1/(4c), F(0,1/(4c)) directrix y = -1/(4c) 
3. {{{y= (1/4)(x + 3)^2 + 5}}}V(-3,5),a = 1/4,   p = 1/4a = 1,  F(0,6) directrix y = 4