I'm a college student with an college level Intermediate Algebra question:

Which are the following are not functions?

  1. y = x2

  2. y = x3

  3. x = y2

  4. y = 3

Your help is greatly appreciated.

Thank you,

Hi Christian,

Try graphing these relations and applying the vertical line test. Imagine a series of vertical lines superimposed over the graphs. If any of these vertical lines goes through the graph more than once, it is not a function. If each vertical line goes through the graph at most once, it is a function.

Hope this helps,


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