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

 It is currently 05 Dec 2013, 18:03

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If x<>0 and x=^(1/2) , then, in terms of y, x= (A) 2y

Author Message
TAGS:
Senior Manager
Joined: 22 May 2003
Posts: 336
Location: Uruguay
Followers: 1

Kudos [?]: 1 [0], given: 0

If x<>0 and x=^(1/2) , then, in terms of y, x= (A) 2y [#permalink]  08 Sep 2003, 10:58
If x<>0 and x=[ 4xy - 4(y^2) ]^(1/2) , then, in terms of y, x=

(A) 2y
(B) y
(C) y/2
(D) (-4(y^2))/(1-4y)
(E) -2y

Any ideas on how to solve this WITHOUT backsolving?
CEO
Joined: 15 Aug 2003
Posts: 3477
Followers: 56

Kudos [?]: 641 [0], given: 781

Re: Square root Problem [#permalink]  08 Sep 2003, 14:48
MartinMag wrote:
If x<>0 and x=[ 4xy - 4(y^2) ]^(1/2) , then, in terms of y, x=

(A) 2y
(B) y
(C) y/2
(D) (-4(y^2))/(1-4y)
(E) -2y

Any ideas on how to solve this WITHOUT backsolving?

Step 1..

x^2 = 4xy - 4y^2

Step 2

x^2 - 4xy + 4y^2 = 0

Step 3

(x - 2y) ^2 = 0

Step 4

x -2y = 0

therefore x =2y

thanks
praetorian
Senior Manager
Joined: 22 May 2003
Posts: 336
Location: Uruguay
Followers: 1

Kudos [?]: 1 [0], given: 0

Step 2

x^2 - 4xy + 4y^2 = 0

Step 3

(x - 2y) ^2 = 0

NICE MOVE!!! Thanks
Similar topics Replies Last post
Similar
Topics:
Is x+2y > 0 1. x/(x+2y) > 0 2. y/(x+2y) > 0 1 30 Mar 2004, 16:25
X^2 * Y > 0 ? 3 25 Oct 2006, 11:19
If x not equal to -y, is (x-y)/(x+y) <1>0 (2) y<0 1 06 Aug 2007, 19:06
If x#-y, is x-y/x+y > 1? 1.) x > 0 2.) y < 0 These 1 02 Mar 2009, 17:51
8 If x#-y is (x-y)/(x+y)>1? (1) x>0 (2) y<0 14 19 Jun 2010, 02:45
Display posts from previous: Sort by