Question 135170
find the equation of a line parallel/perpendicular without a point that it goes through? 
example: y=3x+9 (I don't have a point that it goes through) 
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The given line has a slope of 3
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"ANY" line parallel to the given line must have slope = 3. e.g. y = 3x+k
where k is any number.
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"ANY" line perpendicular to the given line must have slope = -1/3. 
e.g. y (-1/3)x + k where k is any number
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Cheers,
Stan H.