Step 1:
\The vertex of parabola is
.
The focus of parabola is
.
Since x - coordinate of focus is zero, then axis of parabola is vertical.
\The standard form of vertical parabola with center at origin
.
Where focus
.
in this case 
Substitute
in
.
The parabola equation is
.
Solution:
\The parabola equation is
.