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In the xyplane, region R consists of all the points (x, y)
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17 Sep 2008, 10:49
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In the xyplane, region R consists of all the points (x, y) such that 2x + 3y = 6. Is the point (r, s) in region R ? (1) 3r + 2s = 6 (2) r = 3 and s = 2 == Message from GMAT Club Team == This is not a quality discussion. It has been retired. If you would like to discuss this question please repost it in the respective forum. Thank you! To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative  Verbal Please note  we may remove posts that do not follow our posting guidelines. Thank you.



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Re: DSCordinate Geometry
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17 Sep 2008, 10:59
vivektripathi wrote: In the xyplane, region R consists of all the points (x, y) such that 2x + 3y = 6. Is the point (r, s) in region R ? (1) 3r + 2s = 6 (2) r = 3 and s = 2 IMO E R consists of all the points that satisfy 2x + 3y = 6 R can consis of other points also ,hence (1) and (2) are not SUFFI IMO E
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Re: DSCordinate Geometry
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17 Sep 2008, 12:10
cant we put r = 3 and s = 2 in the equation 2x + 3y = 6 and see if it satisfied it.
and similarly see if same points satisfy the equation in A and the one in the q.
isnt the answer D?
what am i missing?
Jack



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Re: DSCordinate Geometry
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17 Sep 2008, 14:38
(r,s) must satisfy 2r+3s = 6 if it is in region R (I don't think the question implies that R could contain other points than those on this line). (1) => 3r +2s =6 but we want to know if 2r +3s = 6 . This is true if (r,s) = (6/5,6/5), and false otherwise... INSUFF.
(2) => 2(3) + 3(2) = 12 which isn't equal to 6. This tells us (r,s) isn't in R. SUFF.
IMO : (B)



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Re: DSCordinate Geometry
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17 Sep 2008, 23:07
Region R essentially means all the points on the line 2x + 3y = 6. If, I plot this line in XY plane, it will meet Xaxis at (3,0) and Yaxis at (0,2).
Now stmt1 gives a line that meets Xaxis at (2,0) and Yaxis at (0,3). This line definitely intersects the original line at one point. Hence, this is insufficient as only for one combination of r and s, this satisfies the original equation. For other combinations, it does not.
stmt 2: this is a point clearly not on the original line. Hence, sufficient.
Hence, B.



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Re: DSCordinate Geometry
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18 Sep 2008, 07:50
Hi Vivek, Well answer cannot be E at least when stmt 2 clearly says (r,s) doesnt lie on R



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Re: DSCordinate Geometry
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18 Sep 2008, 08:20
vivektripathi wrote: In the xyplane, region R consists of all the points (x, y) such that 2x + 3y = 6. Is the point (r, s) in region R ? (1) 3r + 2s = 6 (2) r = 3 and s = 2 Looks like we are missing something in this question.. region R consists of all the points (x, y) such that 2x + 3y = 6  this is line not a region.. so I believe we are missing <= or >= then it may be region. ( 2x + 3y <= 6 or 2x + 3y >= 6 represents region)
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Re: DSCordinate Geometry
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Updated on: 18 Sep 2008, 10:47
The equation 2x + 3y = 6 represent the line, it can not represent the region........ question itself might be wrong.....however it appeared to me as it is and that's why i could not understood it. the source is unknowm (some papers in PDF Form)
Originally posted by vivektripathi on 18 Sep 2008, 08:27.
Last edited by vivektripathi on 18 Sep 2008, 10:47, edited 1 time in total.



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Re: DSCordinate Geometry
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18 Sep 2008, 08:37
vivektripathi wrote: The equation 2x + 3y = 6 represent the line, it can not represent the region........ question itself might be wrong.....however it appeared to as it is and that's why i could understood it. What is the source of this question? == Message from GMAT Club Team == This is not a quality discussion. It has been retired. If you would like to discuss this question please repost it in the respective forum. Thank you! To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative  Verbal Please note  we may remove posts that do not follow our posting guidelines. Thank you.
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Re: DSCordinate Geometry &nbs
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