Answer
Refer to the image below for the graph.
Work Step by Step
The given interval involves a close parentheses.
This means that the upper limit (which is $-3$) is not included in the set.
The given interval is unbounded on the left.
Therefore, the given interval is equivalent to:
$x \lt -3$
To graph this on a number line, plot a hollow dot (or a hole) at $-3$, then shade the region to its left.
(Refer to the attached image in the answer part above.)