Answers:
Domain = 2, 3, 6
Range = 70, 80, 90, 100
Is it a function? No
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Step-by-step explanation:
To determine the domain, we simply list the x coordinates.
The x coordinates of the given points is {6, 2, 6, 3}
Let's sort the values and toss out duplicates to end up with a domain of {2, 3, 6}
Since your teacher has already typed curly braces for you, all you need to do is enter the domain values separated by commas. Though just keep the curly braces in mind.
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The range handles the y coordinates.
The y coordinates of the points from left to right are {90, 70, 80, 100} which sorts to {70, 80, 90, 100} which is the range.
We don't have any duplicates this time.
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Now to answer whether or not this is a function.
Note the x value x = 6 repeats itself. Since this occurs, it means the input x = 6 produces more than one output. This is not allowed if we wanted a function. A function is only possible if any x input produces exactly one output only.
If you were to graph the points, then you'd find that (6,90) and (6,80) fail the vertical line test. This is a quick way to visually see if we have a function or not.
Whichever method you prefer, the conclusion should be "No, this isn't a function". We would need to get rid of either (6,90) or (6,80) from the set of points to end up with a function.