Answer: Choice A) {-1, 0, 1, 3}
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Explanation:
To get the domain, list the x coordinate of each point shown.
The points on that graph are (-1, 1), (0, -2), (1, 3) and (3, 0). We see the x coordinates are: -1, 0, 1 and 3
Therefore, the domain is {-1, 0, 1, 3} which is choice A. The curly braces indicate we have a set of values. The domain is the set of all possible x inputs.