Answer:
The domain and range is (as inequalities):

Or in interval notation:
![D=(-\infty, 3]\text{ and } R=(-\infty, \infty)](https://img.qammunity.org/2022/formulas/mathematics/high-school/7ohi3oeujkr209f0vsudwz20xqzw9pzx6c.png)
Explanation:
Recall that the domain is simply the set of all x-values of the function.
From the graph, we can see that the function is defined for all x-values less than or equal to 3.
Therefore, the domain is:

The range is the set of all y-values of the function.
From the graph, we can see that the range will extend infinitely in both directions.
Therefore, the range is all real numbers. As an inequality:

Or in interval notation, the domain is:
![(-\infty, 3]](https://img.qammunity.org/2022/formulas/mathematics/college/v5idolzs0egvqb9c9nu1zj21ruzrok2ogs.png)
And the range is:
