Answer
Vertex: $(0,0)$
Focus: $(0,-3)$
Directrix: $y=3$
Work Step by Step
Recall: The parabola $x^2=4y$ has a vertex $(0,0)$, a focus $(0,p)$, and a directrix $y=-p$.
We have $x^2+12y=0$ or equivalently $x^2=-12y$.
Then,
$4p=-12$ $p=\frac{-12}{4}$ $p=-3$
So, the vertex is $(0,0)$, the focus is $(0,-3)$, and the directrix is $y=3$.
Sketch the graph:
