Last visit was: 12 Sep 2026, 16:41 It is currently 12 Sep 2026, 16:41
Home
Messages
Tests
Schools
Events
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
Hoozan
User avatar
Joined: 28 Sep 2018
Last visit: 30 Dec 2025
Posts: 642
Own Kudos:
749
 [1]
Given Kudos: 248
GMAT 1: 660 Q48 V33 (Online)
GMAT 2: 700 Q49 V37
Products:
My Reviews
GMAT 2: 700 Q49 V37
Posts: 642
Kudos: 749
 [1]
If a b, what is the value of a + b? (1) a^2 - b^2 = 6 (2) ab = 12 Updated on: 27 Mar 2022, 02:03
Originally posted by Hoozan on 24 Mar 2022, 01:45.
Last edited by Hoozan on 27 Mar 2022, 02:03, edited 1 time in total.
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

35% (medium)

Question Stats:

67% (01:05) correct 33% (01:34) wrong based on 78 sessions

History

Date
Time
Result
Not Attempted Yet
If a ≠ b, what is the value of a + b?

(1) a^2 - b^2 = 0
(2) ab = 12

This Question is Locked Due to Poor Quality
Hi there,
The question you've reached has been archived due to not meeting our community quality standards. No more replies are possible here.
Looking for better-quality questions? Check out the 'Similar Questions' block below for a list of similar but high-quality questions.
Want to join other relevant Problem Solving discussions? Visit our Data Sufficiency (DS) Forum for the most recent and top-quality discussions.
Thank you for understanding, and happy exploring!
ShowHide Answer
Official Answer
A
Pure algebraic questions like this one are no longer part of the GMAT Data Sufficiency syllabus.
For relevant Data Sufficiency questions, please check the Data Sufficiency forum:
Data Sufficiency Forum
User avatar
Hoozan
User avatar
Joined: 28 Sep 2018
Last visit: 30 Dec 2025
Posts: 642
Own Kudos:
749
Given Kudos: 248
GMAT 1: 660 Q48 V33 (Online)
GMAT 2: 700 Q49 V37
Products:
My Reviews
GMAT 2: 700 Q49 V37
Posts: 642
Kudos: 749
If a b, what is the value of a + b? (1) a^2 - b^2 = 6 (2) ab = 12 24 Mar 2022, 01:46
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Similar Question: https://gmatclub.com/forum/if-a-b-what- ... 08684.html
User avatar
Charli08
User avatar
Joined: 09 Sep 2021
Last visit: 12 Dec 2022
Posts: 134
Own Kudos:
99
Given Kudos: 33
Location: Bouvet Island
Posts: 134
Kudos: 99
If a b, what is the value of a + b? (1) a^2 - b^2 = 6 (2) ab = 12 26 Mar 2022, 14:40
Kudos
Add Kudos
Bookmarks
Bookmark this Post
The solution to the question as it currently stands is incorrect. The answer should be E.

Question: If a ≠ b, what is the value of a + b?

(1) a^2 - b^2 = 6
This can further be broken down into:
(a+b)(a-b) = 6
We cannot get a numerical answer for this.

(2) ab = 12
Here we can many solutions including fractions and negatives:
2*6
36*1/3

Taking the two together once again we don't have an answer.
Please check the question or let me know if I am missing something.
User avatar
Hoozan
User avatar
Joined: 28 Sep 2018
Last visit: 30 Dec 2025
Posts: 642
Own Kudos:
749
Given Kudos: 248
GMAT 1: 660 Q48 V33 (Online)
GMAT 2: 700 Q49 V37
Products:
My Reviews
GMAT 2: 700 Q49 V37
Posts: 642
Kudos: 749
If a b, what is the value of a + b? (1) a^2 - b^2 = 6 (2) ab = 12 27 Mar 2022, 02:03
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Charli08
The solution to the question as it currently stands is incorrect. The answer should be E.

Question: If a ≠ b, what is the value of a + b?

(1) a^2 - b^2 = 6
This can further be broken down into:
(a+b)(a-b) = 6
We cannot get a numerical answer for this.

(2) ab = 12
Here we can many solutions including fractions and negatives:
2*6
36*1/3

Taking the two together once again we don't have an answer.
Please check the question or let me know if I am missing something.
Show more


I have made the changes to the question. the (1) statement says a^2 - b^2 = 0 and not "6"
User avatar
dhruvadityajain
User avatar
Joined: 01 Dec 2022
Last visit: 03 Sep 2023
Posts: 6
Own Kudos:
9
Given Kudos: 12
Status:online
Affiliations: -------
Location: India
---: ----
Concentration: Real Estate, Sustainability
GPA: 3
WE:Architecture (Real Estate)
Posts: 6
Kudos: 9
If a b, what is the value of a + b? (1) a^2 - b^2 = 6 (2) ab = 12 15 May 2023, 12:36
Kudos
Add Kudos
Bookmarks
Bookmark this Post
(1) a^2 - b^2 = 0

(a-b)(a+b)=0

so either a-b=0 or a+b=0 but a-b can't be zero ( Given a ≠ b)
A = Suff

(2) ab = 12
a x b = 3 x 4 or 12 x 1 or 6x2 , multiple answers are possible so B = Insufficient
User avatar
SamzayWarrior
User avatar
Joined: 07 Jun 2022
Last visit: 12 Jan 2025
Posts: 15
Own Kudos:
10
 [1]
Given Kudos: 70
Location: India
Posts: 15
Kudos: 10
 [1]
If a b, what is the value of a + b? (1) a^2 - b^2 = 6 (2) ab = 12 21 Jan 2024, 04:46
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hoozan
If a ≠ b, what is the value of a + b?

(1) a^2 - b^2 = 0
(2) ab = 12
Show more

Hoozan
I think both the statements are inconsistent with each other. As per statement 1, we know a+b=0 (also sufficient statement)
Now for statement 2 analysis, if -
(a+b)^2= a^2 + b^2 +2ab = 0 (from 1)
so, a^2 + b ^2 = -24 ----> Not possible as the sum of 2 squares can't be negative.

As far as I know even if one of the statements is insufficient, they shouldn't be inconsistent with each other.
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 12 Sep 2026
Posts: 113,479
Own Kudos:
840,898
Given Kudos: 111,485
Products:
GMAT Club Tests
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 113,479
Kudos: 840,898
If a b, what is the value of a + b? (1) a^2 - b^2 = 6 (2) ab = 12 21 Jan 2024, 11:08
Kudos
Add Kudos
Bookmarks
Bookmark this Post
SamzayWarrior
Hoozan
If a ≠ b, what is the value of a + b?

(1) a^2 - b^2 = 0
(2) ab = 12

Hoozan
I think both the statements are inconsistent with each other. As per statement 1, we know a+b=0 (also sufficient statement)
Now for statement 2 analysis, if -
(a+b)^2= a^2 + b^2 +2ab = 0 (from 1)
so, a^2 + b ^2 = -24 ----> Not possible as the sum of 2 squares can't be negative.

As far as I know even if one of the statements is insufficient, they shouldn't be inconsistent with each other.
Show more

a^2 - b^2 = 0 and ab = 12 has two sets of (a, b) satisfying it: \(a = -2\sqrt{3}, \ b = -2\sqrt{3}\) and \(a = 2\sqrt{3}, \ b =2\sqrt{3}\). However, for both of these sets, a = b, which contradicts the info given in the stem.

So, yes, you are right, the question is flawed. Tagging it as Poor Quality and locking.

Thank you!

This Question is Locked Due to Poor Quality
Hi there,
The question you've reached has been archived due to not meeting our community quality standards. No more replies are possible here.
Looking for better-quality questions? Check out the 'Similar Questions' block below for a list of similar but high-quality questions.
Want to join other relevant Problem Solving discussions? Visit our Data Sufficiency (DS) Forum for the most recent and top-quality discussions.
Thank you for understanding, and happy exploring!
Moderator:
Bunuel
Math Expert
113479 posts