Question 1167982
{{{x^2+2y-4=0}}}

{{{2(y-2)=-x^2}}}

{{{-x^2=2(y-2)}}}

vertex is at  (0,2).



{{{4p=2}}}
{{{p=1/2}}}


Since parabola opens downward with vertex maximum, directrix is at {{{y=2&1/2}}}.