x^2=y^2 functions

Question

determine whether each equation defines y as a function of x

Answer 1

x^2=y^2

 

sqrt(y^2) = sqrt(x^2)

 

abs(y) = abs(x)

 

y = ±x

 

Since there are two values of y for each value of x,

y is not a function of x.

 

y is a relation of x. Here are four points that satisfy the original relation:

(-2, -2), (-2, +2), (+2, +2), (+2, -2).

Answer 2

Steve's answer is correct