DS -1

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DS -1

by sparsh.21 » Tue Jan 13, 2009 9:35 am
In the xy-plane, what is the slope of line l?

(1) Line l does not intersect the line with equation y = 1 - x.
(2) Line l intersects the line with equation y = x – 1.


OA is A

please explain the answer
Source: — Data Sufficiency |

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by DavoodBeater » Tue Jan 13, 2009 11:51 am
if (in a plan) two line are not parallel, they must intersect at one point at least
so:
state 1:
SUFF and slope is the same as the other line.
state 2:
INSUFF, exactly opposite side of the first line explanation(if the two lines are not parallel so they must intersect) and there are uncountable line that intersect another line.
Hence: A

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by yalanand » Tue Jan 13, 2009 11:56 am
A is the right choice because

1) states that both the lines never meet which is possible only when both of the lines are parallel to each other...which means slopes of both the lines are same...

2) Slope can be any value...

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by welcome » Tue Jan 13, 2009 3:16 pm
A) if 2 lines are not intersacting to each other, then they are parallal. so slop of both the lines is equal.

B) Intersacting line can make any angle with each other so it is not sure about there slop.

Ans : A
Shubham.
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