Question 700142
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No can do.  *[tex \LARGE x\ =\ -3] is a vertical line, hence any line parallel to it must also be vertical.  All vertical lines have an undefined slope, so you cannot write an equation in slope-intercept form if the slope number is undefined.  Also, with the exception of the line *[tex \LARGE x\ =\ 0], all vertical lines are parallel to and do not intersect the *[tex \LARGE y]-axis.  This means that the *[tex \LARGE y]-intercept does not exist or, in the singular case of *[tex \LARGE x\ =\ 0], there are infinite *[tex \LARGE y]-intercepts so the *[tex \LARGE y]-coordinate of the *[tex \LARGE y]-intercept would be impossible to uniquely specify in a slope-intercept form equation.


However, you can write an equation, albeit not in slope-intercept form, that represents the desired line.  An equation for ANY vertical line is of the form *[tex \LARGE x\ =\ a] where *[tex \LARGE a] is the *[tex \LARGE x]-coordinate of any point through which the line passes.  Since you are given the point *[tex \LARGE (4,2)] you have enough information to write the desired equation.


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
<font face="Math1" size="+2">Egw to Beta kai to Sigma</font>
My calculator said it, I believe it, that settles it
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