Is triangle ABC with sides a, b and c acute angled?

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Is triangle ABC with sides a, b and c acute angled?

1. Triangle with sides a^2, b^2, c^2 has an area of 140 sq cms.
2. Median AD to side BC is equal to altitude AE to side BC.

Answer is A

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by [email protected] » Sat Jan 24, 2015 5:08 pm
Hi pratiksha1234,

What is the source of this question? I ask because the "style" with which it's written (and some of the content) does not match the typical style that GMAT writers use.

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by pratiksha1234 » Sun Jan 25, 2015 7:43 am
Hey Rich,

https://www.questionbank.4gmat.com/mba_p ... ds_9.shtml This is the site I was practising questions from yesterday. So basically, this is out of the scope of the GMAT then?

Pratiksha
[email protected] wrote:Hi pratiksha1234,

What is the source of this question? I ask because the "style" with which it's written (and some of the content) does not match the typical style that GMAT writers use.

GMAT assassins aren't born, they're made,
Rich

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by Brent@GMATPrepNow » Sun Jan 25, 2015 10:14 am
pratiksha1234 wrote:Is triangle ABC with sides a, b and c acute angled?

1. Triangle with sides a^2, b^2, c^2 has an area of 140 sq cms.
2. Median AD to side BC is equal to altitude AE to side BC.

Answer is A
This question is poorly worded.
Is triangle ABC acute angled? This question is ambiguous.
If it means, "Does the triangle contain an acute angle?" then the answer is ALWAYS YES (without even examining the statements). Every triangle in the universe has at least 2 acute angles.
If this means, "Are all 3 angles acute?" then the answer is maybe.
Official GMAT questions are worded to avoid any possible ambiguity.

Here's a recent article about GMAT-worthy practice questions: https://www.gmatprepnow.com/articles/questions-questions

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by [email protected] » Sun Jan 25, 2015 12:06 pm
Hi pratiksha1234,

Have you used any of the Official GMAC material? You'll be far better served with that material (or material from more reputable sources) than the source that you listed.

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by Matt@VeritasPrep » Sun Jan 25, 2015 5:05 pm
Brent@GMATPrepNow wrote: This question is poorly worded.
Is triangle ABC acute angled? This question is ambiguous.
Well, not really. Since every ∆ has at least two acute angles, the question is either trivial ("yes, no matter what") or intended to ask whether all three of the ∆'s angles are acute. Since no DS question can be trivial (= answerable without the statements), it must be the latter.

The question does seem incorrect as worded, however. Simply having an area of 140 wouldn't make for an acute-angled triangle: for instance, suppose I have a right isosceles ∆ with legs of length 2√70. Then a² = 280, b² = 280, and c² = 560, but my ∆ is not acute-angled. Did the problem specify that a, b, and c are integers?