GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 17 Aug 2018, 13:56

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Are all the angles of triangle ABC less than 90 degrees? (1) AB^2 + B

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

DS Forum Moderator
avatar
P
Joined: 22 Aug 2013
Posts: 1342
Location: India
Premium Member
Are all the angles of triangle ABC less than 90 degrees? (1) AB^2 + B  [#permalink]

Show Tags

New post 21 Jul 2018, 21:44
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

37% (01:21) correct 63% (00:59) wrong based on 27 sessions

HideShow timer Statistics

Are all the angles of triangle ABC less than 90 degrees?

(1) AB^2 + BC^2 > AC^2

(2) BC^2 + AC^2 > AB^2
Senior Manager
Senior Manager
avatar
G
Joined: 31 Jul 2017
Posts: 402
Location: Malaysia
WE: Consulting (Energy and Utilities)
Re: Are all the angles of triangle ABC less than 90 degrees? (1) AB^2 + B  [#permalink]

Show Tags

New post 21 Jul 2018, 22:46
amanvermagmat wrote:
Are all the angles of triangle ABC less than 90 degrees?

(1) AB^2 + BC^2 > AC^2

(2) BC^2 + AC^2 > AB^2


From Statement I: B < 90

From Statement II: C < 90

Combining I & II:

We cannot decide if Angle A < or > 90. Hence, E.
_________________

If my Post helps you in Gaining Knowledge, Help me with KUDOS.. !!

DS Forum Moderator
User avatar
P
Joined: 27 Oct 2017
Posts: 673
Location: India
Concentration: International Business, General Management
GPA: 3.64
WE: Business Development (Energy and Utilities)
Premium Member CAT Tests
Re: Are all the angles of triangle ABC less than 90 degrees? (1) AB^2 + B  [#permalink]

Show Tags

New post 23 Jul 2018, 07:20
1

CONCEPT: How to find the nature of angles in a triangle.


If \(a^2+b^2 < c^2\), it means the angle between side a & b is obtuse, the triangle is obtuse.
If \(a^2+b^2 > c^2\), it means the angle between a & b is acute, but since other angle can be obtuse, the triangle cant be taken as acute.
If \(a^2+b^2 =c^2\), it means the angle between a & b is 90 deg, hence the triangle is right.

Solution:
Statement 1) AB^2 + BC^2 > AC^2
it means angle B is acute, No other information.
INSUFFICIENT.

Statement 2) BC^2 + AC^2 > AB^2
it means angle C is acute, No other information.
INSUFFICIENT.

Even Combing Statement 1 & 2, we get angle B & C are acute, but angle A can be Acute, 90 deg or Obtuse.
Angles (A, B, C) can be (60,60,60) or (30,60, 90) or (30,50,100)
Hence INSUFFICIENT.

Answer - E

Attachment:
gmatbusters.jpg
gmatbusters.jpg [ 120.91 KiB | Viewed 143 times ]


Must Do similar questions based on same logic:
1) https://gmatclub.com/forum/is-triangle-abc-with-sides-a-b-and-c-acute-angled-263435.html?hilit=acute
2) https://gmatclub.com/forum/is-triangle-abc-obtuse-angled-203020.html?hilit=acute
3) https://gmatclub.com/forum/are-all-angles-of-triangle-abc-smaller-than-90-degrees-129298.html?hilit=acute
_________________

SC: Confusable words
All you need for Quant, GMAT PS Question Directory,GMAT DS Question Directory
Error log/Key Concepts
Combination Concept: Division into groups
Question of the Day (QOTD)
Free GMAT CATS

Re: Are all the angles of triangle ABC less than 90 degrees? (1) AB^2 + B &nbs [#permalink] 23 Jul 2018, 07:20
Display posts from previous: Sort by

Are all the angles of triangle ABC less than 90 degrees? (1) AB^2 + B

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.