Answer
Please see the graph.
Work Step by Step
$y \leq-x^2+3$
We pick the point $(0,0$ to determine what side of the graph to shade.
$y \leq-x^2+3$
$0 \leq-0^2+3$
$0 \leq 0+3$
$0 \leq 3$ (true, so we shade the side of the graph with the point)