Question 284494
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If the slopes are negative reciprocals of each other, the two lines are perpendicular.


If the slopes are equal but the intercepts unequal, the lines are parallel and do not coincide.


If the slopes are equal and the intercepts are also equal, the lines coincide.


Otherwise, the lines simply intersect somewhere.  


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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