It is currently 21 Oct 2017, 14:36

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Is x = 5?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41892

Kudos [?]: 129158 [0], given: 12194

Is x = 5? [#permalink]

Show Tags

New post 14 Aug 2017, 06:18
Expert's post
5
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

43% (00:34) correct 57% (00:38) wrong based on 79 sessions

HideShow timer Statistics

Kudos [?]: 129158 [0], given: 12194

Manager
Manager
avatar
B
Joined: 20 Jun 2014
Posts: 54

Kudos [?]: 12 [0], given: 24

GMAT 1: 630 Q49 V27
GMAT 2: 660 Q49 V32
Reviews Badge
Re: Is x = 5? [#permalink]

Show Tags

New post 14 Aug 2017, 06:43
From A x = 0 or x = 5 not sufficient
From B x = 0 or x = -5
So sufficient B.

Kudos [?]: 12 [0], given: 24

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41892

Kudos [?]: 129158 [0], given: 12194

Re: Is x = 5? [#permalink]

Show Tags

New post 14 Aug 2017, 07:37
Bunuel wrote:
Is x = 5?

(1) \(x^2-5x=0\)

(2) \(2x^2+10x=0\)


Is x=5?

(1) \(x^2-5x=0\) --> \(x(x-5)=0\) --> \(x=0\) OR \(x=5\). Not sufficient, to answer whether \(x=5\).

(2) \(2x^2+10x=0\) --> \(x(x+5)=0\) --> \(x=0\) OR \(x=-5\). Here we know that \(x\neq{5}\), hence sufficient.

Answer: B.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 129158 [0], given: 12194

Expert Post
Target Test Prep Representative
User avatar
S
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 1648

Kudos [?]: 848 [0], given: 3

Location: United States (CA)
Re: Is x = 5? [#permalink]

Show Tags

New post 24 Aug 2017, 13:37
Bunuel wrote:
Is x = 5?

(1) \(x^2-5x=0\)

(2) \(2x^2+10x=0\)


We need to determine whether x = 5.

Statement One Alone:

x^2 - 5x = 0

x^2 - 5x = 0

x(x - 5) = 0

x = 0 or x = 5

Since x could be either 0 or 5, statement one is not sufficient to answer the question.

Statement Two Alone:

2x^2 + 10x = 0

2x^2 + 10x = 0

2x(x + 5) = 0

x = 0 or x = - 5

Since x could be either 0 or -5, x will never equal 5. Statement two is sufficient to answer the question.

Answer: B
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Kudos [?]: 848 [0], given: 3

Intern
Intern
avatar
B
Joined: 08 Feb 2015
Posts: 25

Kudos [?]: 1 [0], given: 244

Re: Is x = 5? [#permalink]

Show Tags

New post 26 Aug 2017, 03:35
B. As we know it will not be 5. Statement 1 gives 0,5 (insufficient)


Sent from my iPhone using GMAT Club Forum

Kudos [?]: 1 [0], given: 244

Re: Is x = 5?   [#permalink] 26 Aug 2017, 03:35
Display posts from previous: Sort by

Is x = 5?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.