Question 929903
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 , 
the focus is (h,k + p), With Directrix y = (k - p), a = 1/(4p)
..........
parabola with a vertex of (9,-6) and a point of (2,5)
y = a(x-9)^2 - 6
5 = a(-7)^2 - 6
11/49 = a
y = (11/49)(x-9)^2 - 6

{{{drawing(300,300,   -10,20,-10,10,  blue(line(9,10,9,-10))  ,  
 grid(1),
circle(9, -6,0.4),
graph( 300, 300, -10,20,-10,10,0, (11/49)(x-9)^2 - 6))}}}