Question 1014943
A function requires a unique y value for each x value. 
An inequality allows for multiple solutions, so you have multiple y values for a given x value so it's not a function.
Example:
{{{y>x}}}
So for {{{x=1}}}, {{{y=2}}} is a solution and so is {{{y=3}}} etc. so it's not a unique y for each x value so it's not a function.