Answer
Y is not a function of x for this equation.
Work Step by Step
This question asks whether the equation defines y as a function of x (one-to-one function)
$x + y^2 = 14$
$y^2 = 14-x$
$y = +/- \sqrt{14-x}$
For one value of x, there are two values of y, so y is not a function of x for this equation.