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

It is currently 22 Sep 2014, 22:50

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 8xy^3 + 8x^3*y=2x^2*y^2/ 2^-3,what is the value of x?

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Manager
Manager
User avatar
Status: Never ever give up on yourself.Period.
Joined: 23 Aug 2012
Posts: 138
Location: India
Concentration: Finance, Human Resources
Schools: Mays '16
GMAT 1: 570 Q47 V21
GMAT 2: 690 Q50 V33
GPA: 3.5
WE: Information Technology (Investment Banking)
Followers: 8

Kudos [?]: 84 [0], given: 35

If 8xy^3 + 8x^3*y=2x^2*y^2/ 2^-3,what is the value of x? [#permalink] New post 24 Dec 2012, 05:18
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

41% (02:51) correct 59% (02:03) wrong based on 64 sessions
If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} , what is the value of xy?

(1) y > x
(2) x < 0
[Reveal] Spoiler: OA

_________________

Don't give up on yourself ever. Period.
Beat it, no one wants to be defeated (My journey from 570 to 690) : beat-it-no-one-wants-to-be-defeated-journey-570-to-149968.html

Expert Post
2 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 22969
Followers: 3516

Kudos [?]: 26708 [2] , given: 2714

Re: If 8xy^3 + 8x^3*y=2x^2*y^2/ 2^-3,what is the value of x? [#permalink] New post 24 Dec 2012, 05:32
2
This post received
KUDOS
Expert's post
If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}}, what is the value of xy?

8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} --> 8xy^3 + 8x^3y=8*2x^2y^2=0 --> reduce by 8 and re-arrange: xy^3+x^3y-2x^2y^2 --> factor out xy: xy(y^2+x^2-2xy)=0 --> xy(y-x)^2=0 --> xy=0 or y-x=0.

(1) y > x. Since y>x, then y-x\neq{0}, thus xy=0. Sufficient.

(2) x < 0. Not sufficient.

Answer: A.
_________________

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 Dec 2012
Posts: 2
Followers: 0

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

Re: If 8xy^3 + 8x^3*y=2x^2*y^2/ 2^-3,what is the value of x? [#permalink] New post 25 Dec 2012, 12:18
Bunuel wrote:
If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}}, what is the value of xy?

8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} --> 8xy^3 + 8x^3y=8*2x^2y^2=0 --> reduce by 8 and re-arrange: xy^3+x^3y-2x^2y^2 --> factor out xy: xy(y^2+x^2-2xy)=0 --> xy(y-x)^2=0 --> xy=0 or y-x=0.

(1) y > x. Since y>x, then y-x\neq{0}, thus xy=0. Sufficient.

(2) x < 0. Not sufficient.

Answer: A.


This solution does not answer to the question. Question asks about value xy.
if y>x then xy can't be equal 0. It can't be discussed.
Really I don't understand your solution please explain
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 22969
Followers: 3516

Kudos [?]: 26708 [0], given: 2714

Re: If 8xy^3 + 8x^3*y=2x^2*y^2/ 2^-3,what is the value of x? [#permalink] New post 26 Dec 2012, 02:43
Expert's post
akshin wrote:
Bunuel wrote:
If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}}, what is the value of xy?

8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} --> 8xy^3 + 8x^3y=8*2x^2y^2=0 --> reduce by 8 and re-arrange: xy^3+x^3y-2x^2y^2 --> factor out xy: xy(y^2+x^2-2xy)=0 --> xy(y-x)^2=0 --> xy=0 or y-x=0.

(1) y > x. Since y>x, then y-x\neq{0}, thus xy=0. Sufficient.

(2) x < 0. Not sufficient.

Answer: A.


This solution does not answer to the question. Question asks about value xy.
if y>x then xy can't be equal 0. It can't be discussed.
Really I don't understand your solution please explain


You should read a solution carefully.

From the stem we have that either xy=0 or y-x=0.

(1) says that y > x, so y - x > 0, which means that y-x\neq{0}, thus xy=0.
_________________

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

Senior Manager
Senior Manager
avatar
Joined: 16 Feb 2012
Posts: 260
Concentration: Finance, Economics
Followers: 4

Kudos [?]: 67 [0], given: 114

GMAT ToolKit User
If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} , what is the value [#permalink] New post 30 May 2013, 01:16
If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} , what is the value of xy?

(1) y > x
(2) x < 0
_________________

Kudos if you like the post!

Failing to plan is planning to fail.

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 22969
Followers: 3516

Kudos [?]: 26708 [0], given: 2714

Re: If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} , what is the value [#permalink] New post 30 May 2013, 01:19
Expert's post
Re: If 8xy^3 + 8x^3y=\frac{2x^2y^2}{2^{-3}} , what is the value   [#permalink] 30 May 2013, 01:19
    Similar topics Author Replies Last post
Similar
Topics:
7 Experts publish their posts in the topic If 1/3 < z < 2/3, then what is the value of z? iwillcrackgmat 3 09 Mar 2012, 09:37
4 Experts publish their posts in the topic 8xy^3 + 8x^3y = 2x^2*y^2 / 2^(-3), What is xy? dvinoth86 6 23 Feb 2012, 19:27
2 8x y^3 + 8x^3 y = 2x^2y^2 * 8 , What is xy? (1) y > x (2) gmatpapa 4 31 Mar 2011, 11:00
Experts publish their posts in the topic Value of x rxs0005 4 20 Sep 2010, 11:45
2 Experts publish their posts in the topic 8x*y^3 + 8x^3*y = 2x^2*y^2 / 2^(-3), What is xy? GK_Gmat 16 07 Oct 2007, 23:37
Display posts from previous: Sort by

If 8xy^3 + 8x^3*y=2x^2*y^2/ 2^-3,what is the value of 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®.