Find all School-related info fast with the new School-Specific MBA Forum

It is currently 27 Aug 2015, 21:51
GMAT Club Tests

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

A small, rectangular park has a perimeter of 560 feet and a

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Senior Manager
Senior Manager
User avatar
Joined: 08 Jun 2004
Posts: 498
Location: Europe
Followers: 1

Kudos [?]: 27 [0], given: 0

A small, rectangular park has a perimeter of 560 feet and a [#permalink] New post 24 Apr 2006, 12:15
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

A small, rectangular park has a perimeter of 560 feet and a diagonal measurement of 200 feet. What is its area, in square feet?

A. 19,200
B. 19,600
C. 20,000
D. 20,400
E. 20,800
Manager
Manager
avatar
Joined: 20 Mar 2005
Posts: 201
Location: Colombia, South America
Followers: 1

Kudos [?]: 8 [0], given: 0

Re: PS: Area. [#permalink] New post 24 Apr 2006, 12:24
M8 wrote:
A small, rectangular park has a perimeter of 560 feet and a diagonal measurement of 200 feet. What is its area, in square feet?

A. 19,200
B. 19,600
C. 20,000
D. 20,400
E. 20,800


we want to find xy = ?

2x + 2y = 560
x+y = 280

x^2 + y^2 = (200)^2

(x+y)^2 - x^2 - y^2 = 2xy

so (280)^2 - (200)^2 = 2xy

= 38400 / 2 = 19200

so A
Manager
Manager
avatar
Joined: 13 Dec 2005
Posts: 224
Location: Milwaukee,WI
Followers: 1

Kudos [?]: 8 [0], given: 0

 [#permalink] New post 24 Apr 2006, 12:28
2 * (l +b) = 560 so l +b =280

also l^2 +b^2 = 200 ^2

(l +b) ^2 = l^2 +b^2 + 2* l *b

so l*b = ( (l +b) ^2 - (l^2 +b^2 )) /2

((280) ^2 - (200)^2) /2

= 19,200
Senior Manager
Senior Manager
User avatar
Joined: 08 Jun 2004
Posts: 498
Location: Europe
Followers: 1

Kudos [?]: 27 [0], given: 0

 [#permalink] New post 25 Apr 2006, 10:45
Yes the OA is 'A' - 19200,
Both of you guys are correct, nice explanations, but why do you use this expression (l +b) ^2 to receive a quadratic equation?
Manager
Manager
avatar
Joined: 23 Jan 2006
Posts: 192
Followers: 1

Kudos [?]: 12 [0], given: 0

Re: PS: Area. [#permalink] New post 25 Apr 2006, 11:04
conocieur wrote:
(x+y)^2 - x^2 - y^2 = 2xy


ipc302 wrote:
(l +b) ^2 = l^2 +b^2 + 2* l *b


looks like you both are doing the same thing here. Where are you getting that from? just by multiplying out (l+w)^2?
Re: PS: Area.   [#permalink] 25 Apr 2006, 11:04
Display posts from previous: Sort by

A small, rectangular park has a perimeter of 560 feet and a

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.