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

It is currently 04 May 2016, 11:31
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

Is │x│=│y│? (1) x - y = 6 (2) x + y = 0

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

Hide Tags

2 KUDOS received
Intern
Intern
avatar
Joined: 15 Apr 2010
Posts: 48
Followers: 0

Kudos [?]: 24 [2] , given: 11

Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 02 Jul 2012, 21:25
2
This post received
KUDOS
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

68% (01:36) correct 32% (00:45) wrong based on 409 sessions

HideShow timer Statictics

Is │x│=│y│?

(1) x - y = 6
(2) x + y = 0
[Reveal] Spoiler: OA
2 KUDOS received
Senior Manager
Senior Manager
User avatar
Joined: 29 Mar 2012
Posts: 287
Concentration: Entrepreneurship
GMAT 1: 640 Q50 V26
GMAT 2: 660 Q50 V28
GMAT 3: 730 Q50 V38
Followers: 25

Kudos [?]: 318 [2] , given: 23

GMAT ToolKit User
Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 02 Jul 2012, 21:38
2
This post received
KUDOS
Hi,

Using (1),
x-y=6
x=3, y=-3
then, |x|=|y|
but when x=9, y=3
\(|x| \neq |y|\). Insufficient.

Using (2),
x+y=0
or x = -y, when y=1, x=-1
and |x|=|y|, Sufficient.

Thus, Answer (B)

Regards,
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 32621
Followers: 5653

Kudos [?]: 68633 [0], given: 9816

Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 02 Jul 2012, 23:38
Expert's post
1
This post was
BOOKMARKED
Manager
Manager
avatar
Joined: 04 Mar 2013
Posts: 91
Location: India
Concentration: General Management, Marketing
GPA: 3.49
WE: Web Development (Computer Software)
Followers: 0

Kudos [?]: 7 [0], given: 6

Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 16 May 2013, 09:34
catennacio wrote:
Is │x│=│y│?

(1) x - y = 6
(2) x + y = 0




x= y + 6 stmt1

x= -y -> !x! = !y! so stmt1 is the answer B is the choice :)
Senior Manager
Senior Manager
User avatar
Joined: 13 May 2013
Posts: 472
Followers: 2

Kudos [?]: 126 [0], given: 134

Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 12 Jun 2013, 12:07
My first instinct was to manipulate |x|=|y|

x=y
OR
x=-y

1.) says that x-y=6 which means we can get values for x and y

x=6+y
y=x-6

So, for x=y

6+y=y
6=0 (Invalid)

x=x-6
0=6 (Invalid)

So, for x=-y

6+y=-y
y=-3

x=-x+6
x=3

Why wouldn't we use that methodology on this problem?
1 KUDOS received
VP
VP
User avatar
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1123
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Followers: 168

Kudos [?]: 1686 [1] , given: 219

GMAT ToolKit User
Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 12 Jun 2013, 12:27
1
This post received
KUDOS
WholeLottaLove wrote:
My first instinct was to manipulate |x|=|y|

x=y
OR
x=-y

1.) says that x-y=6 which means we can get values for x and y

x=6+y
y=x-6

So, for x=y

6+y=y
6=0 (Invalid)

x=x-6
0=6 (Invalid)

So, for x=-y

6+y=-y
y=-3

x=-x+6
x=3

Why wouldn't we use that methodology on this problem?


Are you saying that A is sufficient?

In the case \(x=3\) and \(y=-3\) => \(|x|=|y|\).

But if \(x=90\) and \(y=84\) then x - y = 6 but \(|x|\neq{|y|}\).

The question asks you if x=y OR x=-y, you cannot assume that it's true in your solution to find the values of x,y for which it holds ture.
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

Senior Manager
Senior Manager
User avatar
Joined: 13 May 2013
Posts: 472
Followers: 2

Kudos [?]: 126 [0], given: 134

Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 12 Jun 2013, 12:43
I should have worded that better.

I guess that solving the problem they way I did, I would say A is correct.

I see that for x-y=6 there could be many values for x and y, however, it seems like many similar problems are solved by manipulating statements (i.e. x-y=6) and plugging into x=y or x=-y.

I understand how this problem was solved, but I want to understand WHY it was solved the way it was.

As always, thank you for for help.


Zarrolou wrote:
WholeLottaLove wrote:
My first instinct was to manipulate |x|=|y|

x=y
OR
x=-y

1.) says that x-y=6 which means we can get values for x and y

x=6+y
y=x-6

So, for x=y

6+y=y
6=0 (Invalid)

x=x-6
0=6 (Invalid)

So, for x=-y

6+y=-y
y=-3

x=-x+6
x=3

Why wouldn't we use that methodology on this problem?


Are you saying that A is sufficient?

In the case \(x=3\) and \(y=-3\) => \(|x|=|y|\).

But if \(x=90\) and \(y=84\) then x - y = 6 but \(|x|\neq{|y|}\).

The question asks you if x=y OR x=-y, you cannot assume that it's true in your solution to find the values of x,y for which it holds ture.
Expert Post
1 KUDOS received
Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Joined: 10 Oct 2012
Posts: 630
Followers: 72

Kudos [?]: 923 [1] , given: 136

Premium Member
Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 12 Jun 2013, 12:48
1
This post received
KUDOS
Expert's post
WholeLottaLove wrote:
My first instinct was to manipulate |x|=|y|

x=y
OR
x=-y

1.) says that x-y=6 which means we can get values for x and y

x=6+y
y=x-6

So, for x=y

6+y=y
6=0 (Invalid)

x=x-6
0=6 (Invalid)

So, for x=-y

6+y=-y
y=-3

x=-x+6
x=3

Why wouldn't we use that methodology on this problem?


When you assume that x=y and solve the equation [x-y = 6], you WILL get invalid solutions as you got because you have anyways assumed that x=y-->
x-y = 0;which contradicts the given fact.

However, when you assume that x=-y-->x+y=0, you have inherently assumed that |x| IS equal to |y| and now you are just solving for the values of x and y. Thus, the equation [x-y=6] would really not make any difference for this method.( x-y) could equal anything and you would still get |x| = |y|.
_________________

All that is equal and not-Deep Dive In-equality

Hit and Trial for Integral Solutions

Senior Manager
Senior Manager
User avatar
Joined: 13 May 2013
Posts: 472
Followers: 2

Kudos [?]: 126 [0], given: 134

Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 12 Jun 2013, 12:52
Ahhh! That makes sense! I am assuming |x| = |y| when I am trying to verify if it does or does not. Thanks!

vinaymimani wrote:
WholeLottaLove wrote:
My first instinct was to manipulate |x|=|y|

x=y
OR
x=-y

1.) says that x-y=6 which means we can get values for x and y

x=6+y
y=x-6

So, for x=y

6+y=y
6=0 (Invalid)

x=x-6
0=6 (Invalid)

So, for x=-y

6+y=-y
y=-3

x=-x+6
x=3

Why wouldn't we use that methodology on this problem?


When you assume that x=y and solve the equation [x-y = 6], you WILL get invalid solutions as you got because you have anyways assumed that x=y-->
x-y = 0;which contradicts the given fact.

However, when you assume that x=-y-->x+y=0, you have inherently assumed that |x| IS equal to |y| and now you are just solving for the values of x and y. Thus, the equation [x-y=6] would really not make any difference for this method.( x-y) could equal anything and you would still get |x| = |y|.
1 KUDOS received
VP
VP
User avatar
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1123
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Followers: 168

Kudos [?]: 1686 [1] , given: 219

GMAT ToolKit User
Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 12 Jun 2013, 12:53
1
This post received
KUDOS
Yes Wotta you should manipolate the statement to understand the question better.

Is \(|x|=|y|\)? it s like saying is x=y or x=-y?

But once you start analyzing the statement you cannot use that info.
_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 9281
Followers: 455

Kudos [?]: 115 [0], given: 0

Premium Member
Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0 [#permalink]

Show Tags

New post 01 Mar 2015, 15:44
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Re: Is │x│=│y│? (1) x - y = 6 (2) x + y = 0   [#permalink] 01 Mar 2015, 15:44
    Similar topics Author Replies Last post
Similar
Topics:
9 Experts publish their posts in the topic If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x jlgdr 7 01 Feb 2014, 15:05
48 Experts publish their posts in the topic Is xy > 0? (1) x - y > -2 (2) x - 2y < -6 Baten80 19 05 Jun 2011, 05:06
Experts publish their posts in the topic Is xy > 0 ? 1) x - y > -2 2) x - 2y < -6 tradinggenius 4 01 Feb 2011, 02:05
14 Experts publish their posts in the topic Is xy>0? (1) x-y>-2 (2) x-2y<-6 4test1 29 08 Dec 2009, 09:07
10 Experts publish their posts in the topic Is xy > 0? (1) x - y > -2 (2) x - 2y < -6 hasham222 7 03 Aug 2009, 04:11
Display posts from previous: Sort by

Is │x│=│y│? (1) x - y = 6 (2) x + y = 0

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


cron

GMAT Club MBA Forum Home| About| 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®.