Question 940465
Picking as standard form,{{{y=a(x-h)^2+k}}} for simplicity.


h=10 and k=2.


{{{a=(y-k)/(x-h)^2}}}
{{{a=(-9-2)/(0-10)^2}}} using the given y-intercept
{{{a=-11/100}}}


{{{highlight(y=-(11/100)(x-10)^2+2)}}}