Question 469266
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A line is a set of ordered pairs.  A vertical line must consist of ordered pairs where the *[tex \Large x]-coordinates are all equal.  That particular vertical line which is descrbed by the set of all ordered pairs that have an *[tex \Large x]-coordinate equal to *[tex \Large 4] is uniquely described by the equation *[tex \Large x\ =\ 4] because any ordered pair with an *[tex \Large x]-coordinate of *[tex \Large 4], regardless of the value of the *[tex \Large y]-coordinate, will be an element of the solution set of the equation *[tex \Large x\ =\ 4]


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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