well if its an if you have an equally infinite number of x values where clearly no real y exists you'll just have a straight line.
0 points for the reasoning,
1/2 points for the answer.

an equally infinite number of x values
wtf is that supposed to mean?
no real y exists
If there was no real y then there would just be an empty graph
There are 2 real y values: 1 and -1
you'll just have a straight line
You will have 2 lines which aren't even contignious
* Amanieu sends KillJoy back to math class