Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 26 May 2017, 21:05

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

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Is x >= 0 ?

Author Message
TAGS:

Hide Tags

Intern
Joined: 05 Jan 2011
Posts: 3
Followers: 0

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

Is x >= 0 ? [#permalink]

Show Tags

17 Jan 2011, 11:12
00:00

Difficulty:

55% (hard)

Question Stats:

48% (01:51) correct 52% (00:50) wrong based on 104 sessions

HideShow timer Statistics

Is x >= 0 ?

(1) x^2 = 9x
(2) x = -|x|
[Reveal] Spoiler: OA
Math Expert
Joined: 02 Sep 2009
Posts: 38908
Followers: 7739

Kudos [?]: 106258 [0], given: 11618

Show Tags

17 Jan 2011, 11:22
KrishnaK wrote:
Is X >= 0 ?

1) X^2 = 9X
2) X = - |X|

The OA is
[Reveal] Spoiler:
A

Is $$x\geq{0}$$?

(1) x^2 = 9x --> $$x(x-9)=0$$ --> either $$x=0$$ or $$x=9$$, in any case the answer to the question "is $$x\geq{0}$$?" will be YES. Sufficient.

(2) x = - |x| --> $$x$$ can be zero (as $$0=-|0|$$) and in this case answer will be YES or $$x$$ can be any negative number (for example -1, as $$-1=-|-1|$$) and the answer will be NO. Not sufficient.

Hope it's clear.
_________________
Intern
Joined: 05 Jan 2011
Posts: 3
Followers: 0

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

Show Tags

17 Jan 2011, 11:39
Thanks Bunuel. I missed that X can be 0 in 2nd statement.
Similar topics Replies Last post
Similar
Topics:
4 If x ≠ 0, is xy > 0? 8 22 Jun 2015, 06:24
2 Is 5 > x > 0 ? 10 13 Mar 2016, 07:48
1 Is x > 0 ? 3 12 Jan 2016, 02:18
12 Is x > 0? 12 23 Nov 2014, 05:48
2 Is x > 0.05? 9 05 Jul 2015, 09:01
Display posts from previous: Sort by