Last visit was: 25 Apr 2024, 05:36 It is currently 25 Apr 2024, 05:36

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
SORT BY:
Date
Tags:
Difficulty: Sub 505 Levelx   Geometryx                     
Show Tags
Hide Tags
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618928 [15]
Given Kudos: 81595
Send PM
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618928 [2]
Given Kudos: 81595
Send PM
User avatar
Director
Director
Joined: 25 Apr 2012
Posts: 531
Own Kudos [?]: 2284 [1]
Given Kudos: 740
Location: India
GPA: 3.21
WE:Business Development (Other)
Send PM
User avatar
Senior Manager
Senior Manager
Joined: 06 Aug 2011
Posts: 269
Own Kudos [?]: 596 [1]
Given Kudos: 82
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
1
Kudos
its C.


BD will be 4square root 2. (that will be base) * 4/2=8 square root 2.
Manager
Manager
Joined: 20 Dec 2013
Posts: 183
Own Kudos [?]: 290 [1]
Given Kudos: 35
Location: India
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
1
Kudos
Ans C

First we calculate BD by Hypotenuse Theorem:
BD=\sqrt{4^2+4^2}=4\sqrt{2}

Area BCD=1/2 * 4\sqrt{2} * 4= 8\sqrt{2}
Director
Director
Joined: 04 Dec 2015
Posts: 620
Own Kudos [?]: 1585 [2]
Given Kudos: 276
Location: India
Concentration: Technology, Strategy
WE:Information Technology (Consulting)
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
2
Kudos
parkerd wrote:
This question has already been answered, but I just needed clarification on how \sqrt{4^2 + 4^2} = 4\sqrt{2}?


(A) 4√2
(B) 8
(C) 8√2
(D) 16
(E) 16√2


\(\sqrt{4^2 + 4^2}\)

Taking \(4^2\) common, we get;

\(\sqrt{4^2(1+1)}\)

\(\sqrt{4^2(2)}\) ------------ (\(\sqrt{4^2} = 4\))

\(4\sqrt{2}\)

Answer (A)...

Hope its clear now.

_________________
Please Press "+1 Kudos" to appreciate. :)
Senior SC Moderator
Joined: 22 May 2016
Posts: 5330
Own Kudos [?]: 35487 [0]
Given Kudos: 9464
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
Expert Reply
Bunuel wrote:
In the figure above, what is the area of triangular region BCD ?

(A) \(4\sqrt{2}\)
(B) 8
(C) \(8\sqrt{2}\)
(D) 16
(E)\(16\sqrt{2}\)

The area of right triangle BCD is \(\frac{1}{2}b*h\), where b = BC = 4, and h is BD because height must be perpendicular to base. Angle DBC of 90° indicates exactly that.To find length of BD, the hypotenuse of triangle ABD ...

Triangle ABD is an isosceles right triangle having sides in the ratio \(x : x : x\sqrt{2}\).

So to find BD, simply multiply 4 by \(\sqrt{2}\) = \(4\sqrt{2}\).

\((\frac{1}{2})\)\((4)\)\((4\sqrt{2})\)
= \(8\sqrt{2}\)

Answer C
Manager
Manager
Joined: 30 Apr 2013
Posts: 61
Own Kudos [?]: 10 [0]
Given Kudos: 9
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
Can we not consider AD = 4 as the height of the triangle BCD?
Math Expert
Joined: 02 Sep 2009
Posts: 92912
Own Kudos [?]: 618928 [0]
Given Kudos: 81595
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
Expert Reply
santro789 wrote:
Can we not consider AD = 4 as the height of the triangle BCD?


The altitude (height) of a triangle is the perpendicular from the base to the opposite vertex. Does AD satisfy this for triangle BCD?
Manager
Manager
Joined: 03 Aug 2017
Posts: 76
Own Kudos [?]: 25 [0]
Given Kudos: 85
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
Here BDsquare = 4square +4square
(BD)2 = 16+16
BDSquare = 32
BD= Root32
Area of Triangle BCD =( Base*Height )/2
=(4 * Root 32 )/2 =
= root 32 can be written as root 16*root 2 and by solving further
= 2*4*root2 - 8 root 2 = C
Manager
Manager
Joined: 20 Jul 2018
Posts: 68
Own Kudos [?]: 72 [0]
Given Kudos: 19
GPA: 2.87
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
As BAD is 45:45:90 triangle so BD=4*1.44
So area of BCD is = 1*4*4*1.44/2
Area od BCD=8*1.44=4underroot2

Answer C

Posted from my mobile device
GMAT Club Legend
GMAT Club Legend
Joined: 12 Sep 2015
Posts: 6821
Own Kudos [?]: 29925 [4]
Given Kudos: 799
Location: Canada
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
2
Kudos
2
Bookmarks
Expert Reply
Top Contributor
Bunuel wrote:
The Official Guide For GMAT® Quantitative Review, 2ND Edition

Attachment:
Untitled.png
In the figure above, what is the area of triangular region BCD ?

(A) \(4\sqrt{2}\)
(B) 8
(C) \(8\sqrt{2}\)
(D) 16
(E) \(16\sqrt{2}\)


Let x = the length of the hypotenuse of the red right triangle


Since we have a right triangle, we can apply the Pythagorean Theorem
We get: 4² + 4² = x²
Simplify: 16 + 16 = x²
Simplify: 32 = x²
So, x = √32 = 4√2

We get:



Now focus on the blue right triangle...


Area of triangle = (base)(height)/2
So, area = (4√2)(4)/2
= (16√2)/2
= 8√2

Answer: C

Cheers,
Brent
User avatar
Non-Human User
Joined: 09 Sep 2013
Posts: 32667
Own Kudos [?]: 821 [0]
Given Kudos: 0
Send PM
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
GMAT Club Bot
Re: In the figure above, what is the area of triangular region BCD ? [#permalink]
Moderators:
Math Expert
92912 posts
Senior Moderator - Masters Forum
3137 posts

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