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

It is currently 28 Aug 2014, 01:34

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

If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
SVP
SVP
User avatar
Joined: 06 Sep 2013
Posts: 1627
Location: United States
Concentration: Finance
GMAT 1: 710 Q48 V39
WE: Corporate Finance (Investment Banking)
Followers: 11

Kudos [?]: 155 [0], given: 254

GMAT ToolKit User
If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x [#permalink] New post 01 Feb 2014, 14:05
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

50% (01:57) correct 50% (01:17) wrong based on 52 sessions
If x·y≠0, what is the value of x/y?

(1) −|x|=y

(2) −|y|=x
[Reveal] Spoiler: OA
SVP
SVP
User avatar
Joined: 06 Sep 2013
Posts: 1627
Location: United States
Concentration: Finance
GMAT 1: 710 Q48 V39
WE: Corporate Finance (Investment Banking)
Followers: 11

Kudos [?]: 155 [0], given: 254

GMAT ToolKit User
Re: If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x [#permalink] New post 01 Feb 2014, 14:08
What I did was

Statement 1

y + |x| = 0, since x and y are different from zero then it means that x = -y

So the value of -y/y = -1

Sufficient

Statement 2

x+|y|=0, means that y= -x

So the value of -x/x = -1

Sufficient

Hence D

Must be something wrong with this approach, or I may be overlooking something
Would anybody please clarify

Cheers
J
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 22141
Followers: 3407

Kudos [?]: 24895 [1] , given: 2697

Re: If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x [#permalink] New post 02 Feb 2014, 01:50
1
This post received
KUDOS
Expert's post
1
This post was
BOOKMARKED
If x·y≠0, what is the value of x/y?

xy≠0 implies that neither of them is 0.

(1) −|x|=y. Notice that this implies that y must be a negative number.

If x>0, then -x=y --> \frac{x}{y}=-1, for example, consider x=-1 and y=-1.
If x<0, then -(-x)=y --> \frac{x}{y}=1, for example, consider x=1 and y=-1.

Not sufficient.

(2) −|y|=x. Notice that this implies that x must be a negative number.

If y>0, then -y=x --> \frac{x}{y}=-1, for example, consider x=-1 and y=1.
If y<0, then -(-y)=x --> \frac{x}{y}=1, for example, consider x=-1 and y=-1.

Not sufficient.

(1)+(2) Since from (2) we have that x is a negative number, then from (1) -|x|=y, becomes -(-x)=y --> x=y --> x/y=1. Sufficient.

Answer: C.

Hope it's clear.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

Intern
Intern
avatar
Joined: 18 Oct 2013
Posts: 17
Location: India
Concentration: General Management, Operations
GMAT 1: 620 Q V
WE: Engineering (Other)
Followers: 0

Kudos [?]: 6 [0], given: 12

CAT Tests
Re: If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x [#permalink] New post 15 May 2014, 01:47
Bunuel wrote:
If x·y≠0, what is the value of x/y?

xy≠0 implies that neither of them is 0.

(1) −|x|=y. Notice that this implies that y must be a negative number.

If x>0, then -x=y --> \frac{x}{y}=-1, for example, consider x=-1 and y=-1.
If x<0, then -(-x)=y --> \frac{x}{y}=1, for example, consider x=1 and y=-1.


Not sufficient.

(2) −|y|=x. Notice that this implies that x must be a negative number.

If y>0, then -y=x --> \frac{x}{y}=-1, for example, consider x=-1 and y=1.
If y<0, then -(-y)=x --> \frac{x}{y}=1, for example, consider x=-1 and y=-1.

Not sufficient.

(1)+(2) Since from (2) we have that x is a negative number, then from (1) -|x|=y, becomes -(-x)=y --> x=y --> x/y=1. Sufficient.

Answer: C.

Hope it's clear.


Hi Bunuel

I could not really understand how the values of 'x' were obtained in the 1st highlighted text.
From Statement 1, 'y' has to be a negative number. Then, are the values for 'x' to be obtained only by having 'y' as a negative number?

In the 2nd highlighted text, don't we have to consider the value of 'y' too?

Thanks in advance.
1 KUDOS received
Moderator
Moderator
User avatar
Joined: 25 Apr 2012
Posts: 617
Location: India
GPA: 3.21
WE: Business Development (Other)
Followers: 14

Kudos [?]: 270 [1] , given: 653

Premium Member CAT Tests
Re: If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x [#permalink] New post 15 May 2014, 02:13
1
This post received
KUDOS
shaderon wrote:
Bunuel wrote:
If x·y≠0, what is the value of x/y?

xy≠0 implies that neither of them is 0.

(1) −|x|=y. Notice that this implies that y must be a negative number.

If x>0, then -x=y --> \frac{x}{y}=-1, for example, consider x=-1 and y=-1.
If x<0, then -(-x)=y --> \frac{x}{y}=1, for example, consider x=1 and y=-1.


Not sufficient.

(2) −|y|=x. Notice that this implies that x must be a negative number.

If y>0, then -y=x --> \frac{x}{y}=-1, for example, consider x=-1 and y=1.
If y<0, then -(-y)=x --> \frac{x}{y}=1, for example, consider x=-1 and y=-1.

Not sufficient.

(1)+(2) Since from (2) we have that x is a negative number, then from (1) -|x|=y, becomes -(-x)=y --> x=y --> x/y=1. Sufficient.

Answer: C.

Hope it's clear.


Hi Bunuel

I could not really understand how the values of 'x' were obtained in the 1st highlighted text.
From Statement 1, 'y' has to be a negative number. Then, are the values for 'x' to be obtained only by having 'y' as a negative number?

In the 2nd highlighted text, don't we have to consider the value of 'y' too?

Thanks in advance.


If you look at St 1 we are given that −|x|=y or y+|x|=0 -----------> 1

Some important properties about |x|

When x\leq{0} then |x|=-x, or more generally when some \ expression\leq{0} then |some \ expression|={-(some \ expression)}. For example: |-5|=5=-(-5);

When x\geq{0} then |x|=x, or more generally when some \ expression\geq{0} then |some \ expression|={some \ expression}. For example: |5|=5;

Also note that |X|\geq{0}

So from St 1 we have y + (Some positive no. x)= 0 -----> y is a negative no.

Now we need to find x/y and not |x|/y and therefore you need to know x to calculate value of y. What you know from St 1 is that y is a negative no but you don't know whether x is a negative or positive no.

Similarly St 2 −|y|=x means x+|y|=0 ------> This means x is a negative no. but we don't know anything about y. It can be positive or negative

Now when you combine the 2 statements you get both x and y are negative and x=y and thus x/y= 1

Hope it helps
_________________


“If you can't fly then run, if you can't run then walk, if you can't walk then crawl, but whatever you do you have to keep moving forward.”

Re: If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x   [#permalink] 15 May 2014, 02:13
    Similar topics Author Replies Last post
Similar
Topics:
3 Experts publish their posts in the topic If xy≠0, what is the value of (2x + y)/(x - 2y)? manojISB 1 14 Jul 2014, 07:40
1 Experts publish their posts in the topic What is the value of x^2-y^2? (1) x+y=0 (2) x-y=2 SergeNew 2 02 Jan 2011, 13:08
What is the value of xy? 1. y=x+1 2.y=x^2 + 1 marcodonzelli 5 16 Mar 2008, 06:58
Experts publish their posts in the topic If 6xy = yx^2 + 9y, what is the value of xy? (1) y x = 3 (2) tera 3 19 Nov 2007, 23:06
What is the value of X^2 -Y^2? 1. x+y=2x 2. x+y=0 I jamesrwrightiii 4 17 Jul 2006, 20:59
Display posts from previous: Sort by

If x·y≠0, what is the value of x/y? (1) −|x|=y (2) −|y|=x

  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®.