Question 370514
Ans: symmetry to the y-axis.
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Why: The inverse would be symmetric to the x-axis
and would therefore not be a function.
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Example: 
y = x^2 is symmetric to the y-axis.
Its inverse is x = y^2 or y = +/-sqrt(x)
{{{graph(400,300,-10,10,-10,10,x^2)}}}

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Cheers,
Stan H.