Answer
Refer to the image below for the graph.
Work Step by Step
The solutions of the given inequality are the numbers that are less than or equal to $4.5$. The numbers that are less than $4.5$ are to the left of $4.5$.
Thus, to graph the solutions on a number line, plot a solid dot at $x=4.5$ (alternatively, a bracket may be used instead of a solid dot), then shade the region to its left.
(refer to the attached image in the answer portion above)