GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 17 Jul 2018, 18:20

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.

Close

Request Expert Reply

Confirm Cancel

Is y>0?

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

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47037
Is y>0? [#permalink]

Show Tags

New post 21 Aug 2017, 21:49
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

67% (00:49) correct 33% (00:58) wrong based on 43 sessions

HideShow timer Statistics

Director
Director
User avatar
P
Joined: 18 Aug 2016
Posts: 631
Concentration: Strategy, Technology
GMAT 1: 630 Q47 V29
GMAT 2: 740 Q51 V38
GMAT ToolKit User Premium Member Reviews Badge
Is y>0? [#permalink]

Show Tags

New post Updated on: 21 Aug 2017, 23:23
Bunuel wrote:
Is y>0?

(1) x^2−y^2=0

(2) x^2+y^2=0


(1) no information about x hence not sufficient

(2) only possible when x=y=0

Sufficient
B

P.S. Second attempt
_________________

We must try to achieve the best within us


Thanks
Luckisnoexcuse


Originally posted by Luckisnoexcuse on 21 Aug 2017, 22:56.
Last edited by Luckisnoexcuse on 21 Aug 2017, 23:23, edited 1 time in total.
Intern
Intern
avatar
B
Joined: 06 Feb 2016
Posts: 4
Is y>0? [#permalink]

Show Tags

New post 21 Aug 2017, 23:20
Answer is B.

statement 1: x^2-y^2=0; x^2=y^2. there can be infinite numbers where x=y, satisfying statement 1. INSUFFICIENT.

statement 2: x^+y^2=0; x^2=-y^2. as this can never be true except x=y=0 (as square of a number cannot be negative). So we have a definite answer i.e. no. SUFFICIENT.

Thanks
Swapnil Varshney
Manager
Manager
avatar
G
Joined: 30 Dec 2016
Posts: 158
Premium Member Reviews Badge
Re: Is y>0? [#permalink]

Show Tags

New post 22 Aug 2017, 06:43
Is y>0?

(1) x^2−y^2=0

(2) x^2+y^2=0



statement 1

x^2−y^2=0
x^2−y^2 => ( x+y ) ( x-y ) = 0

x+y = 0 and x-y = 0
x = -y and x = y ( no information about x and y ) Insuff.

statement 2

x^2+y^2=0

Now, one thing we know from here that x^2 will always be positive and y^2 will always be positive
So, Sum of two positives can only be zero if both of them are zero.
Hence sufficient . y = 0

Regards

SandySilva
_________________

Regards
SandySilva


____________
Hit kudos if my post helped (:

Re: Is y>0?   [#permalink] 22 Aug 2017, 06:43
Display posts from previous: Sort by

Is y>0?

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

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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®.