graph

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by roger federer » Thu Mar 11, 2010 2:36 pm
In the xy-plane, what is the slope of line l?
(1) Line l dose not intersect the line with equation y = 1 - x.
(2) Line l intersects the line with equation y = x - 1.

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by dchilmak » Thu Mar 11, 2010 5:28 pm
Answer is (B)

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by papgust » Thu Mar 11, 2010 6:00 pm
Moved to data sufficiency!

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by ganeshraj » Thu Mar 11, 2010 8:45 pm
IMO = A

If it doesn't intersect a particular line means it should be parallel to that line.
A parallel line should have the same slope.
Last edited by ganeshraj on Thu Mar 11, 2010 8:48 pm, edited 1 time in total.

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by kstv » Thu Mar 11, 2010 8:47 pm
(1) If it does not intresect then they are parallel line having the same slope. Sufficient.
(2) If they intersect at 90° then the product of the slope is -1. This is not necessary. Insufficient.

IMO A