Question 1197239
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All vertical lines are of the form x = k
k is some constant


In this case, <font color=red>the answer is x = 7</font> since the x coordinate of (7,-2) is 7.


Every point on this vertical line has the same x coordinate.
Two such other points are (7,0) and (7,1)
The x coordinate is fixed, or stuck, at 7.
The y coordinate can be whatever you want.


Side notes: 
The slope of any vertical line is undefined.
We cannot write vertical lines in the form y = mx+b since the slope m is undefined.
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