Last visit was: 19 Nov 2025, 07:58 It is currently 19 Nov 2025, 07:58
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
KarishmaB
Joined: 16 Oct 2010
Last visit: 18 Nov 2025
Posts: 16,267
Own Kudos:
76,994
 [1]
Given Kudos: 482
Location: Pune, India
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 16,267
Kudos: 76,994
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
avatar
robinbjoern
Joined: 22 Mar 2020
Last visit: 13 Aug 2021
Posts: 26
Own Kudos:
Given Kudos: 102
Posts: 26
Kudos: 10
Kudos
Add Kudos
Bookmarks
Bookmark this Post
avatar
GMAT0010
Joined: 17 Sep 2019
Last visit: 08 Dec 2022
Posts: 106
Own Kudos:
Given Kudos: 516
GMAT 1: 710 Q49 V38
GMAT 2: 680 Q49 V33
GMAT 2: 680 Q49 V33
Posts: 106
Kudos: 55
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
BritLee
Joined: 08 Oct 2021
Last visit: 20 Mar 2023
Posts: 5
Given Kudos: 38
Location: Canada
Posts: 5
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
JeffTargetTestPrep
Bunuel
For how many integer values of x, is \(|x – 6| > |3x + 6|\)?

(A) 1

(B) 3

(C) 5

(D) 7

(E) Infinite

To solve an inequality where the absolute value of an expression is greater than (or less than) the absolute value of another expression, we need to find the values that make the absolute values of the two expressions equal to each other. That is, to solve |x – 6| > |3x + 6|, we first need to solve |x – 6| = |3x + 6|. Recall that if |A| = |B|, then either A = B (Case 1) or A = -B (Case 2).

Case 1: When \(x - 6 = 3x + 6\):

\(x - 6 = 3x + 6\)

\(-2x = 12\)

\(x = -6\)

Case 2: When \(x - 6 = -(3x + 6)\):

\(x - 6 = -(3x + 6)\)

\(x - 6 = -3x - 6\)

\(4x = 0\)

\(x = 0\)

These two values, -6 and 0, are the critical values for determining the solution to the given inequality. Now when we place these two values on the number line, we will see that they partition the number line into 3 intervals:

\(x < -6\)

\(-6 < x < 0\)

\(x > 0\)

For each of these intervals, we will pick a value in that interval (for example, for x < -6, we can pick -7) and test whether it satisfies the given inequality. If it does, then EVERY number in that interval will satisfy the inequality. If it doesn’t, then NO numbers in that interval will satisfy the inequality. Recall that our given inequality is |x – 6| > |3x + 6|. Let’s begin testing the intervals.

1) For \(x < -6\), let’s pick x = -7:

|-7 – 6| > |3(-7) + 6| ?

\(|-13| > |-15|\)?

\(13 > 15\) → No!

Thus, no numbers in the interval \(x < -6\)will satisfy \(|x – 6| > |3x + 6|.\)

2) For \(-6 < x < 0\), let’s pick x = -1:

\(|-1 – 6| > |3(-1) + 6|\)?

\(|-7| > |3|\) ?

\(7 > 3\)→ Yes

Thus, every number in the interval \(-6 < x < 0\) will satisfy \(|x – 6| > |3x + 6|.\)

3) For \(x > 0\), let’s pick x = 1:

\(|1 – 6| > |3(1) + 6|\) ?

\(|-5| > |9|\) ?

\(5 > 9\) → No

Thus, no numbers in the interval \(x > 0\) will satisfy \(|x – 6| > |3x + 6|.\)As we can see, the only interval that satisfies \(|x – 6| > |3x + 6|\) is \(-6 < x < 0\). In other words, the solution to \(|x – 6| > |3x + 6|\) is \(6 < x < 0\). In this interval, there are 5 integers: -5, -4, -3, -2, and -1.

Answer: C

Hi, Jeff - thank you for your explanation. For Case 2, why do we not also negate A in finding out the value of x?
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,588
Own Kudos:
Posts: 38,588
Kudos: 1,079
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.
   1   2 
Moderators:
Math Expert
105389 posts
Tuck School Moderator
805 posts