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

It is currently 22 Apr 2019, 05:29

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

If the area of the triangle in the figure above is 100, what is the le

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

Hide Tags

 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 54434
If the area of the triangle in the figure above is 100, what is the le  [#permalink]

Show Tags

New post 19 Aug 2017, 10:06
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

89% (00:52) correct 11% (01:43) wrong based on 75 sessions

HideShow timer Statistics

Senior PS Moderator
User avatar
V
Joined: 26 Feb 2016
Posts: 3386
Location: India
GPA: 3.12
If the area of the triangle in the figure above is 100, what is the le  [#permalink]

Show Tags

New post 19 Aug 2017, 10:14
Image

Since we have BC = 20 and we know that the triangle ABC is right angled at B,

We are also given area of the triangle = 100
Area = \(\frac{1}{2} * Base * Height = 100\)
BC is the Height and let x be the Base(AC)

\(\frac{1}{2}*x*20 = 100\)
\(x = \frac{200}{20}\) => \(x = 10\)

In a right angled triangle, using Pythagoras theorem
\(AB^2 = AC^2 + BC^2\)
\(AB^2 = 400 + 100 = 500\)
\(AB = \sqrt{500} = \sqrt{5*10*10}\)
Therefore the length of AB = \(10\sqrt{5}\) (Option B)
_________________
You've got what it takes, but it will take everything you've got
Senior Manager
Senior Manager
User avatar
P
Joined: 29 Jun 2017
Posts: 454
GPA: 4
WE: Engineering (Transportation)
GMAT ToolKit User Reviews Badge
Re: If the area of the triangle in the figure above is 100, what is the le  [#permalink]

Show Tags

New post 19 Aug 2017, 10:18
Ans is B

0.5 AC x BC = 100 , where AC =20
BC= 10

using pythogoras theorm AC^2+BC^2 =AB^2
AB= √500
= 10√5

hence B is correct
_________________
Give Kudos for correct answer and/or if you like the solution.
Retired Moderator
avatar
D
Joined: 25 Feb 2013
Posts: 1215
Location: India
GPA: 3.82
GMAT ToolKit User Reviews Badge
Re: If the area of the triangle in the figure above is 100, what is the le  [#permalink]

Show Tags

New post 19 Aug 2017, 10:20
Bunuel wrote:
Image
If the area of the triangle in the figure above is 100, what is the length of side AB?

(A) 10√3
(B) 10√5
(C) 20
(D) 24
(E) 25


Attachment:
2017-08-19_2104.png


Area of triangle ABC = \(\frac{1}{2}*BC*AC = 100\)
or,\(\frac{1}{2}*20*AC = 100\). therefore \(AC = 10\)
\(AB\) = \(\sqrt{AC^2 + BC^2}\)

Therefore \(AB\) = \(\sqrt{20^2 + 10^2}\) \(= 10\sqrt{5}\)

Option B
Retired Moderator
avatar
B
Status: On a mountain of skulls, in the castle of pain, I sit on a throne of blood.
Joined: 30 Jul 2013
Posts: 305
GMAT ToolKit User Reviews Badge
Re: If the area of the triangle in the figure above is 100, what is the le  [#permalink]

Show Tags

New post 19 Aug 2017, 10:20
Bunuel wrote:
Image
If the area of the triangle in the figure above is 100, what is the length of side AB?

(A) 10√3
(B) 10√5
(C) 20
(D) 24
(E) 25


Attachment:
2017-08-19_2104.png



100=(1/2)*20*x
x=10

AB is the hypotenuse, therefore
20^2+10^2=(AB)^2
AB^2=500
AB=10√5

Answer: B
Manager
Manager
User avatar
G
Joined: 27 Dec 2016
Posts: 232
Concentration: Marketing, Social Entrepreneurship
GPA: 3.65
WE: Marketing (Education)
Reviews Badge
If the area of the triangle in the figure above is 100, what is the le  [#permalink]

Show Tags

New post 19 Aug 2017, 20:48
Bunuel wrote:
Image
If the area of the triangle in the figure above is 100, what is the length of side AB?

(A) 10√3
(B) 10√5
(C) 20
(D) 24
(E) 25


Attachment:
2017-08-19_2104.png


1. Area = \(\frac{1}{2}\) * base * height.
2. Area = 100 = \(\frac{1}{2}\) * AC * BC. Plug the info, we find AC = 10.
3. Find AB using Pythagoras : AB^2 = AC^2 * BC^2. AB^2 = 500, thus AB = \(10\sqrt{5}\).

Answer is B.
_________________
There's an app for that - Steve Jobs.
GMAT Club Bot
If the area of the triangle in the figure above is 100, what is the le   [#permalink] 19 Aug 2017, 20:48
Display posts from previous: Sort by

If the area of the triangle in the figure above is 100, what is the le

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


Copyright

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®.