Identifying Domain and Range of Ovals with Given Points

AI Thread Summary
The discussion focuses on determining the domain and range of a set of points related to vertical ovals. The points provided are (-1, -4), (8, 0), and (0, -1), leading to confusion about whether to express the domain and range as inequalities or sets. The consensus is that the correct representation is as sets: Domain = {-1, 0, 8} and Range = {-4, -1, 0}. It is emphasized that using inequalities would incorrectly suggest that x can take on any value between -1 and 8. The conclusion is that the domain and range should be defined strictly by the given points.
dakiller
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Homework Statement



There are two vertical ovals, one containing the x-coordinate values and one containing the y-coordinate values. The x-axis values: -1, 8, 0 and the y-axis values: -4, 0, -1

(-1,-4) (8,0) and (0,-1) are the three points.

Homework Equations



I'm not sure this is an equation nor did I see any of these in Algebra II

The Attempt at a Solution



So in my mind I can't decide would I list this like an inequality with:

Domain- -1≤x≤8
Range -1≤y≤8

or would I make it like it is just three points so that?

Domain= {-1,0,8}
Range= {-4,-1,0}

Thank you so much for any assistance in advance!
 
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Can you take a picture and post it?

Based on your description, I think the set notation is better.

Also, are there arrows showing a mapping of X to the values Y? Usually when I say range, I mean the image of the function.
 
dakiller said:

Homework Statement



There are two vertical ovals, one containing the x-coordinate values and one containing the y-coordinate values. The x-axis values: -1, 8, 0 and the y-axis values: -4, 0, -1

(-1,8) (8,0) and (0,-1) are the three points.

That is an incomprehensible statement of the problem. Please give the exact wording from your text.
 
attachment.php?attachmentid=15990&d=1224562371.jpg


Its like this except with the values I gave.
 
dakiller said:


Domain= {-1,0,8}
Range= {-4,-1,0}

Thank you so much for any assistance in advance!


dakiller said:
attachment.php?attachmentid=15990&d=1224562371.jpg


Its like this except with the values I gave.

Your domain that I copied above is correct. I don't see what this has to do with ovals though.
 
In that case your answers, Domain -1≤x≤8 and Range -1≤y≤8, are wrong because they imply that x could be a real number between -1 and 8, for example x= 1.25. The domain is simply the set {-1, 0, 8} and the range is the set {-4, -1, 0}. Yes, it really is that easy!
 
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