SOLUTION: Can you explain how a graph shows whether relations are functions or not functions? I get confused when using the vertical-line test.

Question 82994: Can you explain how a graph shows whether relations are functions or not functions? I get confused when using the vertical-line test.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
If any vertical line intersects the graph more that once the
relation is not a function.
Why?
Because that would imply that for some value of "x" there is
more than one corresponding "y" value. That contrdicts the
definition of a function.
=============
Cheers,
Stan H.
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