Answer: 5
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Explanation:
The range is {2, -1, 5, -8, 9} which sorts to {-8, -1, 2, 5, 9}. This is the set of y coordinates of the points given. Each point is of the form (x,y).
Since the domain and range are the same set in this case, we must have those value mentioned as x coordinates of the points.
The domain is the set of x coordinates of the points given.
The values -8, -1, 2, and 9 are already used as x coordinates. The only thing missing is the 5.
