GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 20 Oct 2018, 03:49

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

If (x − 2)^2 = 100, which of the following could be the value of x + 2

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

Hide Tags

SVP
SVP
User avatar
V
Status: Preparing GMAT
Joined: 02 Nov 2016
Posts: 1732
Location: Pakistan
GPA: 3.39
Premium Member CAT Tests
If (x − 2)^2 = 100, which of the following could be the value of x + 2  [#permalink]

Show Tags

New post 25 Apr 2017, 11:33
1
2
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

82% (01:16) correct 18% (00:48) wrong based on 97 sessions

HideShow timer Statistics

If (x − 2)^2 = 100, which of the following could be the value of x + 2 ?

A. −10
B. −8
C. −6
D. 10
E. 12

_________________

Official PS Practice Questions
Press +1 Kudos if this post is helpful

CEO
CEO
User avatar
D
Joined: 12 Sep 2015
Posts: 3020
Location: Canada
Re: If (x − 2)^2 = 100, which of the following could be the value of x + 2  [#permalink]

Show Tags

New post 25 Apr 2017, 11:40
1
Top Contributor
SajjadAhmad wrote:
If (x − 2)² = 100, which of the following could be the value of x + 2 ?

A. −10
B. −8
C. −6
D. 10
E. 12


If (something)² = 100, then EITHER something = 10 OR something = -10

So, we can conclude that EITHER x − 2 = 10 OR x − 2 = -10

If x − 2 = 10, then x = 12, which means x + 2 = 14
Check answer choices...not there.
Move on.

If x − 2 = -10, then x = -8, which means x + 2 = -6
Check answer choices...BINGO!

Answer:

Cheers,
Brent
_________________

Brent Hanneson – GMATPrepNow.com
Image
Sign up for our free Question of the Day emails

Manager
Manager
avatar
S
Joined: 05 Nov 2016
Posts: 89
GMAT ToolKit User
Re: If (x − 2)^2 = 100, which of the following could be the value of x + 2  [#permalink]

Show Tags

New post 25 Apr 2017, 17:01
By looking into the options, we can see 12 and -8 are the only possible values for the equation.
Asked us to solve X+2, hence 14 or -6 is our answer.

-6 is only present, hence Option C
_________________

Kudos are always welcome ... as well your suggestions

Retired Moderator
avatar
P
Joined: 04 Aug 2016
Posts: 517
Location: India
Concentration: Leadership, Strategy
GPA: 4
WE: Engineering (Telecommunications)
Premium Member
Re: If (x − 2)^2 = 100, which of the following could be the value of x + 2  [#permalink]

Show Tags

New post 25 Apr 2017, 21:48
Method 1: To take square roots and consider positive/negative values.
Method 2: To solve the quadratic equation with roots 12 and -8
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 50004
Re: If (x − 2)^2 = 100, which of the following could be the value of x + 2  [#permalink]

Show Tags

New post 26 Apr 2017, 00:58
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2830
Re: If (x − 2)^2 = 100, which of the following could be the value of x + 2  [#permalink]

Show Tags

New post 29 Apr 2017, 09:01
SajjadAhmad wrote:
If (x − 2)^2 = 100, which of the following could be the value of x + 2 ?

A. −10
B. −8
C. −6
D. 10
E. 12


We can simplify the given equation:

√(x − 2)^2 = √100

|x - 2| = 10

We can now solve for when (x - 2) is positive and when it is negative.

When (x - 2) is positive:

x - 2 = 10

x = 12

When (x - 2) is negative:

-(x - 2) = 10

-x + 2 = 10

-x = 8

x = -8

Thus, x + 2 could equal 12 + 2 = 14 or -8 + 2 = -6.

Answer: C
_________________

Jeffery Miller
Head of GMAT Instruction

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

GMAT Club Bot
Re: If (x − 2)^2 = 100, which of the following could be the value of x + 2 &nbs [#permalink] 29 Apr 2017, 09:01
Display posts from previous: Sort by

If (x − 2)^2 = 100, which of the following could be the value of x + 2

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


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.