For each of the following, determine whether the equation defines y as a function of x.

Question

x=7/y

3x=y^2

x^2+|y|=1

4|x|+y=9

Answer 1

yes

no

no

yes

if it passes the vertical line test, it's a function

if it fails, it's not

if more than 1 output for 1 input it's not a function

with y^2 or |y} there are 2 y values for 1 x value