parabola???

as axis is paralle to y axis
the general form =

(x-h)²=4a(y-k)
when x=0 y=4

hence putting the values

h²=4a(4-k)

when x=1 y=9
hence

(1-h)²=4a(9-k)

when x=-2,y=6

hence (h+2)²=4a(6-k)

now multiply the third equation by (-5/2) and add it to the second equation

u will get

5/2(h-2)²-(h-1)²=(3/2)4a(4-k)

but 4a(4-k)=h²

so we get h=-3/4
now youve got h so u will get the aother two variables just by replacing this value in other equations

thank you satan .
solving it I got the answer.