Question 575504
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A line parallel to the *[tex \Large y]-axis is a vertical line.  Vertical lines have a couple of interesting characteristics.  In the first place, ALL of the *[tex \Large x]-coordinates of the set of ordered pairs that comprise the line have to be identical.  Since all of the *[tex \Large x]-coordinates are equal, no matter which two points you choose for the purposes of computing the slope, the slope fraction will have a zero denominator.  Hence, the slope of any vertical line is undefined.


You can't write the equation of a vertical line in slope-intercept form because the slope quantity is undefined.  However, since the *[tex \Large x]-coordinates of all the points on the line are identical, the equation of a vertical line passing through the point *[tex \Large (a, b)] is uniquely defined by the equation *[tex \Large x\ =\ a]


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