Question 172424
Since x=18, this means that EVERY point on this line will be of the form (18,y) where "y" can be any number. So points like (18,-22), (18,-4), and (18,5) all fall on the line. 



All of these points form a vertical line, which looks like 



{{{ drawing(500, 500, -20, 20, -20, 20,
 graph( 500, 500, -20, 20, -20, 20,0),
 line(18,-20,18,20)

)}}}