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

 It is currently 23 Feb 2019, 16:09

### 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

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

## Events & Promotions

###### Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
• ### FREE Quant Workshop by e-GMAT!

February 24, 2019

February 24, 2019

07:00 AM PST

09:00 AM PST

Get personalized insights on how to achieve your Target Quant Score.
• ### Free GMAT RC Webinar

February 23, 2019

February 23, 2019

07:00 AM PST

09:00 AM PST

Learn reading strategies that can help even non-voracious reader to master GMAT RC. Saturday, February 23rd at 7 AM PT

# ∆ABC is a right-angled isosceles triangle, and ∠B is the right angle

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 53066
∆ABC is a right-angled isosceles triangle, and ∠B is the right angle  [#permalink]

### Show Tags

09 Oct 2018, 00:37
00:00

Difficulty:

5% (low)

Question Stats:

93% (01:00) correct 7% (00:26) wrong based on 57 sessions

### HideShow timer Statistics

∆ABC is a right-angled isosceles triangle, and ∠B is the right angle in the triangle. If AC measures $$7√2$$, then which one of the following would equal the lengths of AB and BC, respectively?

(A) 7, 7
(B) 9, 9
(C) 10, 10
(D) 11, 12
(E) 7, 12

_________________
CEO
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2799
Location: India
GMAT: INSIGHT
Schools: Darden '21
WE: Education (Education)
∆ABC is a right-angled isosceles triangle, and ∠B is the right angle  [#permalink]

### Show Tags

Updated on: 09 Oct 2018, 03:24
1
Bunuel wrote:
∆ABC is a right-angled isosceles triangle, and ∠B is the right angle in the triangle. If AC measures 72√72 , then which one of the following would equal the lengths of AB and BC, respectively?

(A) 7, 7
(B) 9, 9
(C) 10, 10
(D) 11, 12
(E) 7, 12

$$AC = Hypotenuse = a√2 = 7√2$$ where $$a$$ is the side of the triangle i.e. $$AB = BC = a$$

i.e. $$Side, a = 7 =AB = BC$$

_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

ACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Originally posted by GMATinsight on 09 Oct 2018, 03:16.
Last edited by GMATinsight on 09 Oct 2018, 03:24, edited 1 time in total.
Math Expert
Joined: 02 Sep 2009
Posts: 53066
Re: ∆ABC is a right-angled isosceles triangle, and ∠B is the right angle  [#permalink]

### Show Tags

09 Oct 2018, 03:21
GMATinsight wrote:
Bunuel wrote:
∆ABC is a right-angled isosceles triangle, and ∠B is the right angle in the triangle. If AC measures 72√72 , then which one of the following would equal the lengths of AB and BC, respectively?

(A) 7, 7
(B) 9, 9
(C) 10, 10
(D) 11, 12
(E) 7, 12

$$AC = Hypotenuse = a√2 = 72√72$$

i.e. $$Side, a = 72*6 = 432$$

Bunuel As per the given information my answer seems correct but I am sure there is a little type error here.

Copy/paste issue. It's $$7√2$$, not $$72√72$$. Edited. Thank you.
_________________
Director
Joined: 19 Oct 2013
Posts: 508
Location: Kuwait
GPA: 3.2
WE: Engineering (Real Estate)
Re: ∆ABC is a right-angled isosceles triangle, and ∠B is the right angle  [#permalink]

### Show Tags

09 Oct 2018, 04:04
Bunuel wrote:
∆ABC is a right-angled isosceles triangle, and ∠B is the right angle in the triangle. If AC measures $$7√2$$, then which one of the following would equal the lengths of AB and BC, respectively?

(A) 7, 7
(B) 9, 9
(C) 10, 10
(D) 11, 12
(E) 7, 12

A right angled isosceles would be 45:45:90

45:45:90 would be x:x:x$$\sqrt{2}$$

x$$\sqrt{2}$$ = 7$$\sqrt{2}$$
making x be 7

so it would be 7,7

Board of Directors
Status: QA & VA Forum Moderator
Joined: 11 Jun 2011
Posts: 4391
Location: India
GPA: 3.5
Re: ∆ABC is a right-angled isosceles triangle, and ∠B is the right angle  [#permalink]

### Show Tags

09 Oct 2018, 07:21
Bunuel wrote:
∆ABC is a right-angled isosceles triangle, and ∠B is the right angle in the triangle. If AC measures $$7√2$$, then which one of the following would equal the lengths of AB and BC, respectively?

(A) 7, 7
(B) 9, 9
(C) 10, 10
(D) 11, 12
(E) 7, 12

The Triangle is Right angled at B = AC is the Hypotenuse = $$7√2$$

The hypotenuse of a Right isosceles triangle is $$a√2$$ = $$7√2$$

Thus, $$a = 7$$, Answer must be (A) 7,7
_________________

Thanks and Regards

Abhishek....

PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS

How to use Search Function in GMAT Club | Rules for Posting in QA forum | Writing Mathematical Formulas |Rules for Posting in VA forum | Request Expert's Reply ( VA Forum Only )

Target Test Prep Representative
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 4972
Location: United States (CA)
Re: ∆ABC is a right-angled isosceles triangle, and ∠B is the right angle  [#permalink]

### Show Tags

12 Oct 2018, 06:52
Bunuel wrote:
∆ABC is a right-angled isosceles triangle, and ∠B is the right angle in the triangle. If AC measures $$7√2$$, then which one of the following would equal the lengths of AB and BC, respectively?

(A) 7, 7
(B) 9, 9
(C) 10, 10
(D) 11, 12
(E) 7, 12

A 45-45-90 right triangle has side ratios of x : x : x√2,where x√2 is the length of the hypotenuse. We see that triangle ABC can have sides of 7, 7, and 7√2.

_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Manager
Joined: 06 Sep 2018
Posts: 175
Location: Pakistan
Concentration: Finance, Operations
GPA: 2.87
WE: Engineering (Other)
Re: ∆ABC is a right-angled isosceles triangle, and ∠B is the right angle  [#permalink]

### Show Tags

13 Oct 2018, 00:53
according to given information its a $$90-45-45$$ triangle with 90 at B.
length of opposite side to 90 degree is given $$(7\sqrt{2})$$
as lengths of sides in $$90-45-45$$ triangle are $$\sqrt{2}x,x,x$$
So side lengths of other two sides are $$7\sqrt{2}/\sqrt{2}=7$$
_________________

Hitting Kudos is the best way of appreciation.

Eric Thomas, "When you want to succeed as bad as you want to breathe, then you'll be successful."

Re: ∆ABC is a right-angled isosceles triangle, and ∠B is the right angle   [#permalink] 13 Oct 2018, 00:53
Display posts from previous: Sort by