|
Author |
Message |
|
Founder
Status: On Vacation :-)
Affiliations: UA-1K, SPG-G, HH-D
Joined: 04 Dec 2002
Posts: 10396
Location: United States (WA)
GMAT 1: 750 Q49 V42
GPA: 3.5
WE: Information Technology (Hospitality and Tourism)
Followers: 1363
Kudos [?]:
4186
[3] , given: 3117
|
GMAT Diagnostic Test Question 35 [#permalink]
 06 Jun 2009, 23:20
3
This post received
KUDOS
GMAT Diagnostic Test Question 35Field: geometry Difficulty: 700
If vertices of a triangle are A (5, 0), B (x, y) and C (25, 0), what is its area? (1) |x| = y = 10 (2) x = |y| = 10 A. Statement (1) ALONE is sufficient, but Statement (2) ALONE is not sufficient B. Statement (2) ALONE is sufficient, but Statement (1) ALONE is not sufficient C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient D. EACH statement ALONE is sufficient E. Statements (1) and (2) TOGETHER are NOT sufficient
_________________
Founder of GMAT Club
Just starting out with GMAT? Start here... | Want to know your GMAT Score? Try GMAT Score Estimator
Need GMAT Book Recommendations? Best GMAT Books
Co-author of the GMAT Club tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
|
|
|
CEO
Joined: 29 Aug 2007
Posts: 2530
Followers: 41
Kudos [?]:
358
[1] , given: 19
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
10 Jun 2009, 20:08
1
This post received
KUDOS
Explanation
Official Answer: D Statement 1: If |x| = y = 10, y is 10 but x could be -10 or 10. The area is same for x = 10 and x = -10. This is sufficient to answer the question. Statement 2: If x = |y| = 10, x = 10 but y could be 10 or -10 but different value of y does not affect the area of the triangle. This statement is also sufficient to answer the question. Therefore the OA is D.
_________________
Verbal: new-to-the-verbal-forum-please-read-this-first-77546.html
Math: new-to-the-math-forum-please-read-this-first-77764.html
Gmat: everything-you-need-to-prepare-for-the-gmat-revised-77983.html
GT
|
|
|
|
|
|
Intern
Joined: 31 May 2009
Posts: 5
Followers: 0
Kudos [?]:
2
[1] , given: 0
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
18 Jul 2009, 10:21
1
This post received
KUDOS
GMAT TIGER wrote: Explanation
Official Answer: B Statement 1: If |x| = y = 10, y is 10 but x could be -10 or 10. Area is not same for x = 10 and x = -10. This is not sufficient to answer the question. Statement 2: If x = |y| = 10, x = 10 but y could be 10 or -10 but different value of y does not affect the area of the triangle. This statement is sufficient to answer the question. Therefore the OA is B. How can a difference in x co-ordinate will change the area. Coz the y co-ordinate will decide the height of the triangle and it is constant. IMHO the answer should be D.
|
|
|
|
|
|
Intern
Joined: 24 Jun 2009
Posts: 13
Location: New York
Followers: 0
Kudos [?]:
1
[0], given: 0
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
20 Jul 2009, 15:42
kyabe wrote: GMAT TIGER wrote: Explanation
Official Answer: B Statement 1: If |x| = y = 10, y is 10 but x could be -10 or 10. Area is not same for x = 10 and x = -10. This is not sufficient to answer the question. Statement 2: If x = |y| = 10, x = 10 but y could be 10 or -10 but different value of y does not affect the area of the triangle. This statement is sufficient to answer the question. Therefore the OA is B. How can a difference in x co-ordinate will change the area. Coz the y co-ordinate will decide the height of the triangle and it is constant. IMHO the answer should be D. Agree with kyabe. Even when x = -10, you still can calculate the area of the rectangle (area of 350) and subtract the areas of two other triangles (250 total). That leaves you with 100 for the area of the triangle. The answer is D.
|
|
|
|
|
|
Manager
Joined: 14 Aug 2009
Posts: 134
Followers: 2
Kudos [?]:
81
[1] , given: 13
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
21 Aug 2009, 22:58
1
This post received
KUDOS
Answer should be C. 1) B can be two points B1(10, 10) or B2(-10,10) therefore Sabc is not certain 2) B can be B1(10, 10) or B2(10, -10) although AC is certain, but the height from B1 to AC and B2 to AC are not the same. therefore Sabc is not certain put 1) and 2) together, B can only be (10, 10) Sabc can be calculated.
_________________
Kudos me if my reply helps!
|
|
|
|
|
|
Manager
Joined: 22 Aug 2009
Posts: 54
Followers: 0
Kudos [?]:
3
[0], given: 1
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
22 Aug 2009, 19:33
flyingbunny wrote: Answer should be C.
1) B can be two points B1(10, 10) or B2(-10,10)
therefore Sabc is not certain
2) B can be B1(10, 10) or B2(10, -10)
although AC is certain, but the height from B1 to AC and B2 to AC are not the same.
therefore Sabc is not certain
put 1) and 2) together,
B can only be (10, 10)
Sabc can be calculated. The question does not require that you know exactly where the triangle is or what its shape is... only the area is being discussed here... the area is the same for any of the possible locations for B that were mentioned, so the correct answer is D.
|
|
|
|
|
|
Manager
Joined: 22 Aug 2009
Posts: 54
Followers: 0
Kudos [?]:
3
[1] , given: 1
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
22 Aug 2009, 23:53
1
This post received
KUDOS
flyingbunny wrote: Architect wrote: flyingbunny wrote: Answer should be C.
1) B can be two points B1(10, 10) or B2(-10,10)
therefore Sabc is not certain
2) B can be B1(10, 10) or B2(10, -10)
although AC is certain, but the height from B1 to AC and B2 to AC are not the same.
therefore Sabc is not certain
put 1) and 2) together,
B can only be (10, 10)
Sabc can be calculated. The question does not require that you know exactly where the triangle is or what its shape is... only the area is being discussed here... the area is the same for any of the possible locations for B that were mentioned, so the correct answer is D. when B is at different points, the areas are different. If B is (-10,10), Area=100. If B is (10,10), Area=100. If B is (10,-10), Area=100. 100=100=100. Make sense? If not, I can sketch up a diagram and scan it to prove it.
|
|
|
|
|
|
Manager
Joined: 14 Aug 2009
Posts: 134
Followers: 2
Kudos [?]:
81
[0], given: 13
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
23 Aug 2009, 00:14
damn, I didn't read the question clearly. I thought C is (0, 25) when C is (25,0), it is easy. Answer is D.
_________________
Kudos me if my reply helps!
|
|
|
|
|
|
Manager
Joined: 13 Aug 2009
Posts: 208
Followers: 3
Kudos [?]:
60
[0], given: 16
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
03 Sep 2009, 08:49
I agree that the answer is D as well. I spent a lot of time trying to figure this one out.
In short if you assume that two points at (5,0) and (25,0) are the base (which equals 20), you still get the same area regardless of whether the third point is at:
(10,10)
(-10,10)
(10,-10)
(-10,-10)
All that matters is that the height is still 10, because the area of a triange is 1/2*base*height: 1/2*10*20 = 100
|
|
|
|
|
|
Senior Manager
Joined: 08 Dec 2009
Posts: 421
Followers: 4
Kudos [?]:
73
[1] , given: 26
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
10 Feb 2010, 18:57
1
This post received
KUDOS
i was so sure it was D until i saw the answer sheet... made me doubt myself there... then i had to google: area of triangle, and stumbled upon this: http://www.mathopenref.com/trianglearea.htmldoesn't matter what the x coordinate is... as long as your base is fixed, and your height is fixed, area should be the same... but i still have to see it (and drag the coordinates around -- see link above) myself to believe it!!
_________________
kudos if you like me (or my post) 
|
|
|
|
|
|
Manager
Joined: 27 Jul 2010
Posts: 199
Location: Prague
Schools: University of Economics Prague
Followers: 1
Kudos [?]:
10
[2] , given: 15
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
09 Oct 2010, 08:42
2
This post received
KUDOS
The answer is D, both pairs of triangles have the same base and height.
Attachments
triangles.gif [ 12.22 KiB | Viewed 5185 times ]
_________________
You want somethin', go get it. Period!
|
|
|
|
|
|
Intern
Joined: 06 Jul 2011
Posts: 27
Followers: 1
Kudos [?]:
3
[0], given: 8
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
18 Jan 2012, 09:04
Wha? Alright, either I'm totally confused right now or there's something wrong. I made a drawing of the whole thing, these are the 2 triangles that could result from the points stated in A), so (10|10) or (10|-10). I've attached my drawing to this post. Unless I made a mistake, this should be drawn to scale. Each division of the grid on the paper corresponds to 5 units. It is very obvious the area of the orange trinangle (the one resulting from point (-10|10)) is a lot larger than that of the blue triangle (resulting from point (10|10)). Also, if assuming the line connecting (5|0) and (25|0) is the base, it is clearly obvious that the heights of these two triangles are different, after all as far as i know the height should be a line from the point opposite to the base in an angle that is orthogonal to the base. Since the base is not a straight vertical line but rather askew, the point (-10|10) cant be simply mirrored to generate a triangle with an equal area. Does that make sense? Did I make a mistake or is there a flaw in the question?
Attachments
GMAT.jpg [ 44.77 KiB | Viewed 970 times ]
|
|
|
|
|
|
Senior Manager
Joined: 19 Apr 2011
Posts: 283
Schools: Booth,NUS,St.Gallon
Followers: 3
Kudos [?]:
27
[1] , given: 45
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
06 Feb 2012, 23:37
1
This post received
KUDOS
I just want to add some new info .The area of two traingles with the same base and between 2 parallel lines will always be the same.
_________________
+1 if you like my explanation .Thanks 
|
|
|
|
|
|
Intern
Joined: 10 Sep 2012
Posts: 5
Followers: 0
Kudos [?]:
0
[0], given: 2
|
Re: GMAT Diagnostic Test Question 35 [#permalink]
20 Dec 2012, 17:12
ummm, the question is rather tricky.
Before wasting time trying to solve either statements, remember that:
if two statements provide identical information then the correct answer will be either D or E.
It's plain to see that both statements are identical; hence, a question with identical statements can not be A, B, or C.
(1) |x| = y = 10
(2) x = |y| = 10
Answer = D, since each statement is sufficient.
|
|
|
|
|
|
|
Re: GMAT Diagnostic Test Question 35
[#permalink]
20 Dec 2012, 17:12
|
|
|
|
|
|
|
|
|
|
|
close
