It is currently 20 Nov 2017, 10:51

### 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

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

# Events & Promotions

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

# if x and y are different integers and x^2=xy, which of the

Author Message
Manager
Joined: 05 Sep 2007
Posts: 144

Kudos [?]: 52 [0], given: 0

Location: New York
if x and y are different integers and x^2=xy, which of the [#permalink]

### Show Tags

24 Sep 2007, 08:33
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

if x and y are different integers and x^2=xy, which of the following must be true?
1.x=0
2.y=0
3.x=-y
A.1 only
B.2 only
C.3 only
D.1 & 3 only
E.1,2 & 3.

Kudos [?]: 52 [0], given: 0

Director
Joined: 22 Aug 2007
Posts: 566

Kudos [?]: 72 [0], given: 0

### Show Tags

24 Sep 2007, 09:12
el1981 wrote:
if x and y are different integers and x^2=xy, which of the following must be true?
1.x=0
2.y=0
3.x=-y
A.1 only
B.2 only
C.3 only
D.1 & 3 only
E.1,2 & 3.

got A,

I think the key phrase is "X and Y are different intengers".

1: 0^2=O. ANY INTENGER, always true.
2: ANY INTENGER^2=0^2, can not be, cuz if Y is zero, X must be something else, as stem says.
3: (-Y)^2=-Y.Y, can be true only if Y is zero, stem does not give such info.

thus only 1st...

Kudos [?]: 72 [0], given: 0

Current Student
Joined: 28 Dec 2004
Posts: 3345

Kudos [?]: 322 [0], given: 2

Location: New York City
Schools: Wharton'11 HBS'12

### Show Tags

24 Sep 2007, 09:33
I say C..

for any X...and for any Y...

x=-y

x=0 is just a subset of all the possible values of x that would work..

x=-y works for all values of X...

Kudos [?]: 322 [0], given: 2

Director
Joined: 22 Aug 2007
Posts: 566

Kudos [?]: 72 [0], given: 0

### Show Tags

24 Sep 2007, 10:10
fresinha12 wrote:
I say C..

for any X...and for any Y...

x=-y

x=0 is just a subset of all the possible values of x that would work..

x=-y works for all values of X...

Can u please elborate on the text in red...? how is it deducted from the stem?

Kudos [?]: 72 [0], given: 0

Director
Joined: 06 Sep 2006
Posts: 734

Kudos [?]: 49 [0], given: 0

### Show Tags

24 Sep 2007, 10:14
x^2 - xy = 0
x (x -y) = 0
x=0 or x - y = 0; x=y
x=y cant be true because x and y are different integers.
only x=0 stands.
A.

Kudos [?]: 49 [0], given: 0

Manager
Joined: 05 Sep 2007
Posts: 144

Kudos [?]: 52 [0], given: 0

Location: New York

### Show Tags

24 Sep 2007, 10:44
Thank you guys. Now i got it.

Kudos [?]: 52 [0], given: 0

24 Sep 2007, 10:44
Display posts from previous: Sort by

# if x and y are different integers and x^2=xy, which of the

Moderator: chetan2u

 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®.