Slope of line l?

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Slope of line l?

by crackgmat007 » Sun May 10, 2009 7:35 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.

Pls explain the logic. Tx . Answer seems to be A

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by Sunshine85 » Sun May 10, 2009 9:00 pm
The Answer is A.

Stmt 1: If 2 lines do not intersect, they must be parallel. Parallel line have same slope. A is Sufficient.

Stmt 2 : If 2 lines intersect, there are infinate number of values for the slope of the line ( since, all non parallel lines intersect ). But had the statement been Line 1 intersects the line perpendicularly, we can find out the slope of L1. ( Product of slopes of Perpendicular lines = -1 )