Answer:
[tex]\boxed{y=-3}[/tex]
Step-by-step explanation:
The graph of this parabola is shown below. From this graph we know that:
VERTEX:
[tex](h,k)=(0,0)[/tex]
DIRECTIX:
Since the vertex lies on the origin and the parabola opens upward, then the standard form of this parabola is:
[tex]x^2=4py[/tex]
So:
[tex]y=\frac{1}{12}x^2 \\ \\ \therefore 12y=x^2 \ or \ x^2=12y \\ \\ \\ Then: \\ \\ 4p=12 \therefore p=3[/tex]
Then the directrix is:
[tex]y=k-p \\ \\ \therefore y=0-3 \therefore \boxed{y=-3}[/tex]
