Last visit was: 17 Jul 2025, 10:49 It is currently 17 Jul 2025, 10:49
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
GMATBusters
User avatar
GMAT Tutor
Joined: 27 Oct 2017
Last visit: 20 Jun 2025
Posts: 1,926
Own Kudos:
6,420
 [9]
Given Kudos: 241
WE:General Management (Education)
Expert
Expert reply
Posts: 1,926
Kudos: 6,420
 [9]
1
Kudos
Add Kudos
8
Bookmarks
Bookmark this Post
avatar
Gemelo90
Joined: 06 May 2018
Last visit: 11 Oct 2018
Posts: 42
Own Kudos:
Given Kudos: 8
Posts: 42
Kudos: 19
Kudos
Add Kudos
Bookmarks
Bookmark this Post
avatar
adityagupta2102
Joined: 06 May 2018
Last visit: 06 Dec 2020
Posts: 8
Own Kudos:
13
 [1]
Given Kudos: 111
Location: India
WE:Information Technology (Consulting)
Posts: 8
Kudos: 13
 [1]
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
avatar
adityagupta2102
Joined: 06 May 2018
Last visit: 06 Dec 2020
Posts: 8
Own Kudos:
Given Kudos: 111
Location: India
WE:Information Technology (Consulting)
Posts: 8
Kudos: 13
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Gemelo90
I was testing different numbers and came to the conclusion that B always has to be true.
a-b is always greater than 0. Since it involves a square root of a square which is always a positive or a zero.
So a-b > 0
a>b.
User avatar
AkshdeepS
Joined: 13 Apr 2013
Last visit: 10 Jul 2025
Posts: 1,441
Own Kudos:
1,825
 [3]
Given Kudos: 1,001
Status:It's near - I can see.
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE:Engineering (Real Estate)
Products:
Posts: 1,441
Kudos: 1,825
 [3]
2
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
gmatbusters
If \(a-b > \sqrt{(b+c-a)^2}\) which of the following must be true?


A. a>0

B. a<b

C. b=0

D. c>0

E. c<0

Given : \(a-b > \sqrt{(b+c-a)^2}\)

We know that \(\sqrt{(x)^2}\) = \(|x|\)

So, \(a - b > |b+c-a|\)

Therefore we have 2 cases :

Case 1 :

\(a - b > b + c - a\)

\(2a - 2b > c\)

\(a - b > \frac{c}{2}\) (No match)

Case 2:

\(a - b > -(b + c - a)\)

\(a - b > - b - c + a\)

\(a - a - b + b > - c\)

\(0 > - c\)

\(c > 0\)

(D)
User avatar
GMATBusters
User avatar
GMAT Tutor
Joined: 27 Oct 2017
Last visit: 20 Jun 2025
Posts: 1,926
Own Kudos:
6,420
 [3]
Given Kudos: 241
WE:General Management (Education)
Expert
Expert reply
Posts: 1,926
Kudos: 6,420
 [3]
3
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Another Approach:
Attachments

IMG-20180722-WA0000_1532201863144.jpg
IMG-20180722-WA0000_1532201863144.jpg [ 62.51 KiB | Viewed 3628 times ]

User avatar
GMATBusters
User avatar
GMAT Tutor
Joined: 27 Oct 2017
Last visit: 20 Jun 2025
Posts: 1,926
Own Kudos:
6,420
 [2]
Given Kudos: 241
WE:General Management (Education)
Expert
Expert reply
Posts: 1,926
Kudos: 6,420
 [2]
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Another approach:
(a-b) > 0 because square root is always non negative.
therefore, (b-a) < 0
hence c must be >0, so that (b+c-a) is non negative.
(If (b+c-a) is negative, square root is not defined)

Hence, c > 0
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 37,437
Own Kudos:
Posts: 37,437
Kudos: 1,013
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Moderators:
Math Expert
102603 posts
PS Forum Moderator
697 posts