Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 50007

Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
25 Feb 2015, 03:20
Question Stats:
42% (01:34) correct 58% (01:51) wrong based on 403 sessions
HideShow timer Statistics




EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12686
Location: United States (CA)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
25 Feb 2015, 22:44
Hi All, When you're given the lengths of two sides of a triangle, you have no way of knowing what type of triangle you're dealing with. It MIGHT be a right triangle. It MIGHT be isosceles. It MIGHT be a really long, thin triangle that's ALMOST a straight line (but still has 3 distinct sides). As such, you have to find the maximum value for the area; with that, you know that every SMALLER area is also possible. In this type of situation, the maximum area will occur if the two sides form the legs of a right triangle. With these side lengths (6 and 8), we'd have... Area = (1/2)(6)(8) = 24 = maximum possible area Now we know that the range of possible areas is 0 < Area <= 24. So all three values are possible. Final Answer: GMAT assassins aren't born, they're made, Rich
_________________
760+: Learn What GMAT Assassins Do to Score at the Highest Levels Contact Rich at: Rich.C@empowergmat.com
Rich Cohen
CoFounder & GMAT Assassin
Special Offer: Save $75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee www.empowergmat.com/
*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****




Intern
Joined: 19 Jan 2014
Posts: 23
WE: Accounting (Accounting)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
25 Feb 2015, 05:50
I. 2 IMHO this area is impossible, because if this would be possible than the height to the largest side with length of 8 would have to be 2*2/8 = 1/2 Third side would be larger than 2 (because of sides 6 and 8), and i think the height to the largest side will be larger than 1/2
III. 24 This area is possible, 6*8*1/2 = 24
II. 12 Upon analysing answer options without I and with III option there is only one answer: C
Answer is C, II and III are possible areas
p.s. solved very quickly, in less than 20 sec



Math Expert
Joined: 02 Aug 2009
Posts: 6967

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
25 Feb 2015, 07:03
Plastelin wrote: I. 2 IMHO this area is impossible, because if this would be possible than the height to the largest side with length of 8 would have to be 2*2/8 = 1/2 Third side would be larger than 2 (because of sides 6 and 8), and i think the height to the largest side will be larger than 1/2
III. 24 This area is possible, 6*8*1/2 = 24
II. 12 Upon analysing answer options without I and with III option there is only one answer: C
Answer is C, II and III are possible areas
p.s. solved very quickly, in less than 20 sec hi why cant be the height be less than 2... yes the third side has to be more than>2,otherwise it will become a straight line... say the side is just above 2.. then the height can be .1,.2,1/3,1/4 etc so we have base 8 and height 1/8... area =1/2*1/8*8=1/2 .. so 2 is possible
_________________
1) Absolute modulus : http://gmatclub.com/forum/absolutemodulusabetterunderstanding210849.html#p1622372 2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html 3) effects of arithmetic operations : https://gmatclub.com/forum/effectsofarithmeticoperationsonfractions269413.html
GMAT online Tutor



Math Expert
Joined: 02 Aug 2009
Posts: 6967

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
25 Feb 2015, 07:07
Bunuel wrote: Two sides of a triangle have length 6 and 8. Which of the following are possible areas of the triangle?
I. 2 II. 12 III. 24
A. I only B. I and II only C. II and III only D. I and III only E. I, II, and III
Kudos for a correct solution. hi, lets see the minimum value and max value.. 1)min value... two sides are 6,8.. third side has to be more than 2, otherwise we will have a straight line... with height slightly above 2, we can have height as 1/10,1/8,1/2 etc.. so min value can be any positive number, fraction decimal etc... 2) max valve .. lets take these as two sides of a right angle triangle, then area=1/2*8*6=24.. all three values fit in so ans E..
_________________
1) Absolute modulus : http://gmatclub.com/forum/absolutemodulusabetterunderstanding210849.html#p1622372 2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html 3) effects of arithmetic operations : https://gmatclub.com/forum/effectsofarithmeticoperationsonfractions269413.html
GMAT online Tutor



SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1829
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
27 Feb 2015, 02:18
Answer = E. I, II, and III With dimensions of only 2 sides given (for a triangle), this becomes an open ended question Any area is possible out of the three
_________________
Kindly press "+1 Kudos" to appreciate



Math Expert
Joined: 02 Aug 2009
Posts: 6967

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
27 Feb 2015, 02:25
PareshGmat wrote: Answer = E. I, II, and III
With dimensions of only 2 sides given (for a triangle), this becomes an open ended question
Any area is possible out of the three hi paresh, there is a limitation on the upper end of area, which is area of a right angle triangle with these two sides..
_________________
1) Absolute modulus : http://gmatclub.com/forum/absolutemodulusabetterunderstanding210849.html#p1622372 2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html 3) effects of arithmetic operations : https://gmatclub.com/forum/effectsofarithmeticoperationsonfractions269413.html
GMAT online Tutor



SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1829
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)

Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
27 Feb 2015, 02:47
chetan2u wrote: PareshGmat wrote: Answer = E. I, II, and III
With dimensions of only 2 sides given (for a triangle), this becomes an open ended question
Any area is possible out of the three hi paresh, there is a limitation on the upper end of area, which is area of a right angle triangle with these two sides.. Fully agree Chetan... that's why mentioned out of the three given Area is maximum when height is maximum Height is maximum when its a right triangle Attachment:
angle.png [ 4.18 KiB  Viewed 23360 times ]
_________________
Kindly press "+1 Kudos" to appreciate



Math Expert
Joined: 02 Sep 2009
Posts: 50007

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
02 Mar 2015, 05:41
Bunuel wrote: Two sides of a triangle have length 6 and 8. Which of the following are possible areas of the triangle?
I. 2 II. 12 III. 24
A. I only B. I and II only C. II and III only D. I and III only E. I, II, and III
Kudos for a correct solution. MAGOOSH OFFICIAL SOLUTION:This requires a picture explanation. Consider the leg of 6 and the leg of 8 attached at a "hinged" joint at B. Attachment:
originals.jpg [ 15.57 KiB  Viewed 23293 times ]
Here, the angle is made very narrow, only 1/100 of a degree. The area of this triangle would be 0.00419  you don't need to be able to calculate something like this for the test. The point is  if the angle were one millionth, or one billionth, the area could be really really small  greater than zero, but a really tiny decimal. So, clearly, the area can be less than two. Here, I moved the legs of 6 and 8 apart a little, and produced a triangle with an area of exactly two: Attachment:
originals (1).jpg [ 19.59 KiB  Viewed 23299 times ]
Again, you don't have to know how to build a triangle like this: this is just to show you that it is, indeed possible. As we increase the angle, we get triangles with more and more area. You do not need to know how to find these areas  this is just to demonstrate that the area would increase. Attachment:
originals (2).jpg [ 21.71 KiB  Viewed 23302 times ]
Attachment:
originals (3).jpg [ 22.77 KiB  Viewed 23308 times ]
Attachment:
originals (4).jpg [ 22.5 KiB  Viewed 23271 times ]
Now, there's a geometry theorem that states, when the angle is 90°, the area of the triangle will be a maximum. At that point, the length of 8 will be the base, and the length of 6 will be the height, so the area = 0.5*bh = 24, the maximum possible area. Thus, the triangle can have all three areas: I, II, and III. Answer = E.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread  All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
What are GMAT Club Tests? Extrahard Quant Tests with Brilliant Analytics



Math Expert
Joined: 02 Sep 2009
Posts: 50007

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
02 Mar 2015, 05:42



LBS Thread Master
Joined: 13 Jan 2015
Posts: 106
Location: United Kingdom
Concentration: Other, General Management

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
26 Mar 2015, 08:41
Hi Rich, Going with your logic on the areas, and looking at this example iftwosidesofatriangleare12and8whichofthe141227.htmlWhy cant we find possible outcomes for the third leg and then try and see if we get an area Eg, from the link, let third side be x then 128<x<20 so if we assume x to be 16,, and assume the triangle is a right triangle with 12 as the height, Then we can have an area of 1/2*12*16 = 64, therefore the area can be more than 56 Any thoughts??



EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12686
Location: United States (CA)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
26 Mar 2015, 11:24
Hi Tmoni26, You can actually catch the error in this logic yourself. Try drawing the triangle that you describe. What are the 3 sides (and how does this NOT match up with the information in the prompt)? GMAT assassins aren't born, they're made, Rich
_________________
760+: Learn What GMAT Assassins Do to Score at the Highest Levels Contact Rich at: Rich.C@empowergmat.com
Rich Cohen
CoFounder & GMAT Assassin
Special Offer: Save $75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee www.empowergmat.com/
*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****



Intern
Joined: 03 Jul 2015
Posts: 10
Location: India

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
15 Jul 2015, 06:44
PareshGmat wrote: Answer = E. I, II, and III
With dimensions of only 2 sides given (for a triangle), this becomes an open ended question
Any area is possible out of the three Well, there is another way to solve such questions using trignometry. Area of a triangle is \(1/2absin\)(\(\alpha\)), where \(a\) and \(b\) are any two sides of the triangle and \(\alpha\) is the angle contained by these two sides. Now area is maximum when sine function becomes \(1\) at \(\alpha\) \(=\)\(90^{\circ}\). Also area tends to \(0\) as \(\alpha\) approaches \(0^{\circ}\).



EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12686
Location: United States (CA)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
15 Jul 2015, 13:24
Hi ravindra88, You're going to find that most GMAT questions can be solved in a variety of ways, so you should look for whichever method is easiest/fastest for you. It is worth noting, however, that Trigonometry is NOT tested on the GMAT, so choosing to use such an approach is up to you (but is not expected of you). GMAT assassins aren't born, they're made, Rich
_________________
760+: Learn What GMAT Assassins Do to Score at the Highest Levels Contact Rich at: Rich.C@empowergmat.com
Rich Cohen
CoFounder & GMAT Assassin
Special Offer: Save $75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee www.empowergmat.com/
*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****



Board of Directors
Joined: 17 Jul 2014
Posts: 2657
Location: United States (IL)
Concentration: Finance, Economics
GPA: 3.92
WE: General Management (Transportation)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
08 Jan 2016, 19:49
2 ways to solve it: 1  plug in numbers: h=1/2. 1/2*8 /2 = 2. 1 yes. h=1. 1*8/2 = 4. 2 yes. h=6. 6*8/2 = 24. 3 yes.
other method: third side must be greater than 2, less than 14. greatest possible area thus can be almost 14*8/2 or slightly less than 56. everything below  is possible, so long as it is not 0 or negative.



Manager
Joined: 06 Jun 2013
Posts: 160
Location: India
Concentration: Finance, Economics
GPA: 3.6
WE: Engineering (Computer Software)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
02 Jul 2017, 00:29
24 is the one possibility if it is a right angled triangle. once we get this, the only thing we need to do is to change the angle between the two given sides and thus changing the height before it becomes 0 degree or 180 degree (both excluded). so area can be anything based on the height of the triangle.



Director
Joined: 02 Sep 2016
Posts: 697

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
06 Jul 2017, 22:24
I did it this way. Area= 0.5 *base*height We have no clue about the third side. It may not be an integer. We just know that: 2<third side<14 But there are so many values that c can take even in this range. Let's work with the options: 1) Area= 2= 0.5 *b*h b*h= 4 2) b*h= 24 3) b*h= 48 There are many possible values that can result in these products. So I selected all three. Does this make sense?
_________________
Help me make my explanation better by providing a logical feedback.
If you liked the post, HIT KUDOS !!
Don't quit.............Do it.



Intern
Joined: 09 Dec 2013
Posts: 28

Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
Updated on: 11 Feb 2018, 20:31
Shiv2016 wrote: I did it this way.
Area= 0.5 *base*height
We have no clue about the third side. It may not be an integer. We just know that: 2<third side<14
But there are so many values that c can take even in this range.
Let's work with the options:
1) Area= 2= 0.5 *b*h b*h= 4
2) b*h= 24
3) b*h= 48
There are many possible values that can result in these products. So I selected all three.
Does this make sense? Thanks RIch
Originally posted by Buttercup3 on 13 Jul 2017, 21:41.
Last edited by Buttercup3 on 11 Feb 2018, 20:31, edited 1 time in total.



EMPOWERgmat Instructor
Status: GMAT Assassin/CoFounder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 12686
Location: United States (CA)

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
14 Jul 2017, 07:28
Hi Buttercup3, The answer to your question can be found in a number of posts earlier on in the thread. Here's one of them: When you're given the lengths of two sides of a triangle, you have no way of knowing what type of triangle you're dealing with. It MIGHT be a right triangle. It MIGHT be isosceles. It MIGHT be a really long, thin triangle that's ALMOST a straight line (but still has 3 distinct sides). As such, you have to find the maximum value for the area; with that, you know that every SMALLER area is also possible. In this type of situation, the maximum area will occur if the two sides form the legs of a right triangle. With these side lengths (6 and 8), we'd have... Area = (1/2)(6)(8) = 24 = maximum possible area Now we know that the range of possible areas is 0 < Area <= 24. So all three areas (including "2") are possible. GMAT assassins aren't born, they're made, Rich
_________________
760+: Learn What GMAT Assassins Do to Score at the Highest Levels Contact Rich at: Rich.C@empowergmat.com
Rich Cohen
CoFounder & GMAT Assassin
Special Offer: Save $75 + GMAT Club Tests Free
Official GMAT Exam Packs + 70 Pt. Improvement Guarantee www.empowergmat.com/
*****Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!*****



Intern
Joined: 09 Dec 2013
Posts: 28

Re: Two sides of a triangle have length 6 and 8. Which of the following ar
[#permalink]
Show Tags
14 Jul 2017, 09:29
EMPOWERgmatRichC wrote: Hi Buttercup3,
The answer to your question can be found in a number of posts earlier on in the thread. Here's one of them:
When you're given the lengths of two sides of a triangle, you have no way of knowing what type of triangle you're dealing with. It MIGHT be a right triangle. It MIGHT be isosceles. It MIGHT be a really long, thin triangle that's ALMOST a straight line (but still has 3 distinct sides).
As such, you have to find the maximum value for the area; with that, you know that every SMALLER area is also possible. In this type of situation, the maximum area will occur if the two sides form the legs of a right triangle. With these side lengths (6 and 8), we'd have...
Area = (1/2)(6)(8) = 24 = maximum possible area
Now we know that the range of possible areas is 0 < Area <= 24.
So all three areas (including "2") are possible.
GMAT assassins aren't born, they're made, Rich Thank You Sir for the reply




Re: Two sides of a triangle have length 6 and 8. Which of the following ar &nbs
[#permalink]
14 Jul 2017, 09:29



Go to page
1 2
Next
[ 22 posts ]



