Last visit was: 10 Jun 2026, 14:39 It is currently 10 Jun 2026, 14:39
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
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 10 Jun 2026
Posts: 111,192
Own Kudos:
Given Kudos: 106,749
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 111,192
Kudos: 819,956
 [28]
2
Kudos
Add Kudos
26
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 10 Jun 2026
Posts: 111,192
Own Kudos:
819,956
 [2]
Given Kudos: 106,749
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 111,192
Kudos: 819,956
 [2]
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
General Discussion
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 10 Jun 2026
Posts: 11,242
Own Kudos:
45,374
 [2]
Given Kudos: 338
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
Expert
Expert reply
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,242
Kudos: 45,374
 [2]
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
User avatar
Iotaa
User avatar
LBS Moderator
Joined: 25 Apr 2020
Last visit: 15 Mar 2023
Posts: 133
Own Kudos:
Given Kudos: 99
Location: India
Posts: 133
Kudos: 156
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
If \((x + y)^2 < x^2\), which of the following must be true?

I. \(y(y + 2x) < 0\)
II. \(y < x\)
III. \(xy < 0\)

(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I and III only


 


Enjoy this brand new question we just created for the GMAT Club Tests.

To get 1,600 more questions and to learn more visit: user reviews | learn more

 


\((x + y)^2 < x^2\) = \((x + y)^2 - x^2 <0 \)

\(( y)^2 + 2xy <0 \)

y(y+2x) <0; it means either y<0, or y+2x<0 but not together.


I. \(y(y + 2x) < 0\): Correct as we got the same above
II. \(y < x\): two cases, Case I if y<0, in this case x>y. Case 2, if y>0, in this case, x>y. That is not always true.
III. \(xy < 0\): two cases, Case I if y<0, in this case, xy<0. Case 2, if y>0, in this case also, xy<0. Correct

Correct answer is E
User avatar
romasharma1998
Joined: 13 Jan 2022
Last visit: 13 Apr 2025
Posts: 13
Own Kudos:
Given Kudos: 247
Location: India
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi Bunuel

why can't we take square root on both sides? we will end up with x+y<x which simplifies to y<0
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 10 Jun 2026
Posts: 111,192
Own Kudos:
819,956
 [1]
Given Kudos: 106,749
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 111,192
Kudos: 819,956
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
romasharma1998
Hi Bunuel

why can't we take square root on both sides? we will end up with x+y<x which simplifies to y<0

Because \(\sqrt{a^2}=|a|\), not simply a.
User avatar
vasu1104
Joined: 10 Feb 2023
Last visit: 10 Jun 2026
Posts: 526
Own Kudos:
Given Kudos: 671
Location: Canada
Posts: 526
Kudos: 302
Kudos
Add Kudos
Bookmarks
Bookmark this Post
x^2 + 2xy + y^2 < x^2
2xy + y^2 <0
y(2x+y) <0

now we have y< 0 and 2x+y<0

for the second condition x and y have opposite sign for sure.
if x>0, then y<-2
and if x<0, then y>3

option A will always true.
option B cant must be true but could be true.
option C can be true always.

ans E



Bunuel
If \((x + y)^2 < x^2\), which of the following must be true?

I. \(y(y + 2x) < 0\)
II. \(y < x\)
III. \(xy < 0\)

(A) I only
(B) II only
(C) III only
(D) I and II only
(E) I and III only

Experience GMAT Club Test Questions
Yes, you've landed on a GMAT Club Tests question
Craving more? Unlock our full suite of GMAT Club Tests here
Want to experience more? Get a taste of our tests with our free trial today
Rise to the challenge with GMAT Club Tests. Happy practicing!
­
Moderator:
Math Expert
111192 posts