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

 It is currently 26 May 2019, 21:12

### 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

# If AD is 6, and ADC is a right angle, what is the area of

Author Message
Intern
Joined: 21 Jan 2010
Posts: 7

### Show Tags

01 Jun 2010, 05:22
00:00

Difficulty:

(N/A)

Question Stats:

14% (01:58) correct 86% (00:36) wrong based on 6 sessions

### HideShow timer Statistics

If AD is 6, and ADC is a right angle, what is the area of triangular region ABC?

(1) Angle ABD = 60°

(2) AC = 12

OPEN DISCUSSION OF THIS QUESTION IS HERE: http://gmatclub.com/forum/if-ad-is-6-an ... 01200.html

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.

If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.
Current Student
Joined: 29 Apr 2010
Posts: 209
Schools: Sloan R1, McCombs R1, Ross R1 (w/int), Haas R2, Kellogg R2
WE 1: Product Engineering/Manufacturing
Re: If AD is 6, and ADC is a right angle, what is the area of  [#permalink]

### Show Tags

01 Jun 2010, 05:37
Since we know the height (AD), we only need to find the base length (BC)

i: ABD = 60, but we don't know BAC or ACD, so we can only find the length of BD, not BC, which we need.
ii: Again, we can find the length of DC, but not BC.

Combined: Since we can find BD from (i), and DC from (ii), we have BC and can find the area. Answer is C.
Senior Manager
Joined: 25 Feb 2010
Posts: 324
Re: If AD is 6, and ADC is a right angle, what is the area of  [#permalink]

### Show Tags

03 Jun 2010, 18:30

Don't forget some one else will be waiting for answer
Math Expert
Joined: 02 Sep 2009
Posts: 55277
Re: If AD is 6, and ADC is a right angle, what is the area of  [#permalink]

### Show Tags

11 Aug 2017, 02:40
sm0k3rz wrote:

If AD is 6, and ADC is a right angle, what is the area of triangular region ABC?

(1) Angle ABD = 60°

(2) AC = 12

OPEN DISCUSSION OF THIS QUESTION IS HERE: http://gmatclub.com/forum/if-ad-is-6-an ... 01200.html

If AD is 6 and ADC is a right angle, what is the area of triangular region ABC?

Given: $$AD=6$$. Question: $$area_{ABC}=\frac{1}{2}*AD*BC=\frac{1}{2}*6*(BD+DC)=3(BD+DC)=?$$

(1) Angle ABD = 60 --> triangle ABD is 30-60-90 triangle, so the sides are in ratio $$1:\sqrt{3}:2$$ --> as AD=6 (larger leg opposite 60 degrees angle) then $$BD=\frac{6}{\sqrt{3}}$$ (smallest leg opposite 30 degrees angle). But we still don't know DC. Not sufficient.

(2) AC=12, we can find DC. But we still don't know BD. Not sufficient.

(1)+(2) We know both BD and DC, hence we can find area. Sufficient.

OPEN DISCUSSION OF THIS QUESTION IS HERE: http://gmatclub.com/forum/if-ad-is-6-an ... 01200.html

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.

If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.

_________________
Re: If AD is 6, and ADC is a right angle, what is the area of   [#permalink] 11 Aug 2017, 02:40
Display posts from previous: Sort by