BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

DS - Inequality

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Legendary Member
Posts: 1665
Joined: Thu Nov 03, 2011 7:04 pmFollowed by: 70 members
Thanked: 165 times
by karthikpandian19 » Fri Jul 06, 2012 4:20 pm
Is x > -3?

x2 - 9 > x + 3
|x3| < 64
Regards,
Karthik
The source of the questions that i post from JUNE 2013 is from KNEWTON

---If you find my post useful, click "Thank" :) :)---
---Never stop until cracking GMAT---
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
User avatar
Legendary Member
Posts: 520
Joined: Sat Apr 28, 2012 9:12 pmFollowed by: 49 members
Thanked: 339 times
GMAT Score:770

by eagleeye » Fri Jul 06, 2012 5:04 pm
karthikpandian19 wrote:Is x > -3?

x2 - 9 > x + 3
|x3| < 64
We need to find whether x>-3

With that in mind, let's look at statement 1.
x^2-9 > x+3
x^2-3^2 > x+3
(x+3)*(x-3) > (x+3)
(x+3)*(x-3) - (x+3) > 0
(x+3)*(x-3-1)>0
(x+3)*(x-4)>0
From these equations, we get that x < -3 or x > 4. Insufficient.

Statement 2 reads:
|x^3|<64
|x^3|<4^3
|x|<4
-4 < x < 4. x lies between -4 and 4. We don't know whether x > -3 or not. Insufficient.

Together the statements are (x <-3 or x>4 ) AND -4 < x < 4
The only common region is -4 < x < -3, where the two statements are satisfied simultaneously. Hence x < -3, so we know for sure that x is not greater than -3. Sufficient.

Hence C is the answer.

Let me know if this helps :)
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
GMAT Instructor
Posts: 1248
Joined: Thu Mar 29, 2012 2:57 pmFollowed by: 192 members
Location: Everywhere
Thanked: 503 times
GMAT Score:780

by Bill@VeritasPrep » Fri Jul 06, 2012 5:47 pm
Is x > -3?

x2 - 9 > x + 3
|x3| < 64

Statement 1

x2 - 9 > x + 3 (move everything to the left side)

x2 - x - 9 - 3 > 0 (simplify)

x2 - x -12 > 0 (factor by inspection)

(x+3)(x-4) > 0

Either x < -3 or x > 4; insufficient

Statement 2

|x3| < 64

|x3| < 4^3

|x| < 4

x is between -4 and 4; insufficient.

Combined

The only possible values of x that satisfy both conditions are between -4 and -3. Sufficient for us to answer definitely yes.
Join Veritas Prep's 2010 Instructor of the Year, Matt Douglas for GMATT Mondays

Visit the Veritas Prep Blog

Try the FREE Veritas Prep Practice Test
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1