BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

What is the area of rectangular region R ?

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 109
Joined: Sun May 10, 2009 7:53 am

What is the area of rectangular region R ?

by sanjib » Fri Sep 04, 2009 8:19 am
What is the area of rectangular region R ?
(1) Each diagonal of R has length 5.
(2) The perimeter of R is 14.
IMO E
because only 30.60.90 angle situation comply to say that it would be 3:4:5 the both side and Hypt.
However it only angle we know is 90 then it could be any angle and not has to be 30 and 60
Top
Source: — Data Sufficiency |
User avatar
MBA Admissions Consultant
Posts: 1090
Joined: Wed May 27, 2009 4:06 am
Thanked: 175 times
Followed by:68 members
GMAT Score:750

by Bryant@VeritasPrep » Fri Sep 04, 2009 12:29 pm
this seems to me that both together are sufficient since you end up with two equations, two unknowns, namely:

2a+2b = 14
and
a^2 + b^2 = 25

which is solvable
Bryant Michaels
MBA Admissions Consultant


Enroll now. Pay later. Take advantage of Veritas Prep's flexible payment plan options
Top
Senior | Next Rank: 100 Posts
Posts: 65
Joined: Thu Jul 02, 2009 10:38 pm
Location: Bangalore
Thanked: 1 times

by engg.manik » Sat Sep 05, 2009 11:32 am
The correct answer acc to me is C.

as from St 1 a^2 + b^2 = 25

from st 2 - 2a + 2b = 14 ---> (a+b)^2=7^2
solving will get 25 + 2ab = 49
ab = 12 which is the area.

I hope it helps
Top
Legendary Member
Posts: 1578
Joined: Sun Dec 28, 2008 1:49 am
Thanked: 82 times
Followed by:9 members
GMAT Score:720

Re: What is the area of rectangular region R ?

by maihuna » Sat Sep 05, 2009 11:36 am
sanjib wrote:What is the area of rectangular region R ?
(1) Each diagonal of R has length 5.
(2) The perimeter of R is 14.
IMO E
because only 30.60.90 angle situation comply to say that it would be 3:4:5 the both side and Hypt.
However it only angle we know is 90 then it could be any angle and not has to be 30 and 60
diagonal : (a^2+b^2)^1/2 = 5 => a^2+b^2 = 25
Perimeter: 2(a+b) = 14 => a+b = 7

=> a^2+b^2 = (a+b)^2-2ab => 2ab = -a^2+b^2 + (a+b)^2
=> 2ab = -25+49 = 24 => ab = 12 = area C
Charged up again to beat the beast :)
Top
Post new topic Post Reply
• Page 1 of 1