You can put this solution on YOUR website! I must appologize, I don't know what java commands that I need to plug in to get graphs that are not functions, but I can tell you what to do.
x = 4
This is a special case, whenever you have x=k where k is a real number and there's no y, you have a vertical line going through k. (Vertical lines aren't functions, hence I can't graph it.)
In your case you have a vertical line going through 4. So draw your plane:
Now draw a line going up and down through x=4.
Happy Calculating!!!
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