SOLUTION: Problem: Determine whether the equation defines y as a function of x. Explain why or why not. a.) x^2+y=9 b.) x+sqrt(y)=5

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Question 947367: Problem: Determine whether the equation defines y as a function of x. Explain why or why not.
a.) x^2+y=9

b.) x+sqrt(y)=5

Answer by josgarithmetic(39617)   (Show Source): You can put this solution on YOUR website!
Yes to both.

#1 is obvious because you solve for y in terms of x.

#2, less obvious.
, one branch of a parabola.
, and you must have .
square both sides.
, .

The part for which y is non-negative would be the actual graph.



Also multiply the right member.


and that is the same as .

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