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| Question 215995:  would an elipse be a function? why or why not?
 Answer by vleith(2983)
      (Show Source): 
You can put this solution on YOUR website! No, in order to nbe a function, any single input (x) can yield only 1 output (y). Use the vertical line rule. In order to be a function, no vertical line can intersect the plot in more than one place. Ellipse can intersect in 2 places ... so it can't be a function.
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