SOLUTION: Which one of the following is a function? 3x – y^2 = 9 3x – y = 9 3x^2 – y^2 = 9

is not a function because (6,-3) and (6,3) both satisfy
 and a function cannot have two different
y-values for the same x-value.





Also





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Thus for each value of x, there is only one value of y,
since 3x-9 has but one value.

Therefore this is a function

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is not a function because (√6,-3) and (√6,3) both satisfy
 and a function cannot have two different
y-values for the same x-value.






Also







Edwin