Answer
$(-\infty,0]$
Work Step by Step
Since x can be any number less than or equal to 0, the left number in the interval notation is $-\infty$ and the left delimiter is a parenthesis. On the graph, the arrow continues to the left to infinity.
Since 0 is included in the solution set, the right delimiter in interval notation is a square bracket, and the endpoint of the graph is a solid circle.
