GMAT PREP I XY COORDINATE

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GMAT PREP I XY COORDINATE

by pkw209 » Tue Dec 29, 2009 10:16 am
Hey all,

Could figure this one out. A brief explanation would be much appreciated. Thanks!


6) Does line k intersect quadrant II?

a. Slope of k is -1/6
b. Y intercept of k is -6
Source: — Data Sufficiency |

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by funx » Tue Dec 29, 2009 5:55 pm
My guess is that A is the correct answer. If you know that the slope is negative then the line will definitely cross the second quadrant (just draw the system of coordinates and see it for yourself).

(2) is insufficient in my opinion because the line could be upward sloping with the intercept of -6 and not cross the second quadrant. However, it could also be downward sloping in which case it will cross the quadrant, i.e. case (i)

What's the OA?

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by linkinpark » Wed Dec 30, 2009 11:00 am
I think its E

stmt 1 - my guess is there can be many lines with slope -1/6, e.g consider points (1,5) and (7,4) you get a slope -1/6 try these points with different quadrants

stmt 2 - there can be many lines with y=-6 intercept

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by pkw209 » Wed Dec 30, 2009 12:53 pm
you are correct funx, answer is A!

however, i don't see it. technically, wouldn't a positive and negative slope cross all 4 quadrants?

Or, couldn't you have 2 points for line k that exist only in one quadrant?