Answer:
Domain:

Range:

Explanation:
The domain is the span of x-values the graph covers.
The range is the span of y-values the graph covers.
The given graph is a quadratic. We can see that the x-values will extend infinitely in both directions.
Thus, the domain is all real numbers.
In set notation, this is:

From the graph, we can see that the maximum value is y=-2. The graph won't ever go above this.
So, the range is all real numbers less than or equal to -2.
In interval notation, this is:

And we are done :)