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

Redeem

Inequalities

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |
Legendary Member
Posts: 829
Joined: Mon Jul 07, 2008 10:09 pm
Location: INDIA
Thanked: 84 times
Followed by:3 members

Re: Inequalities

by sudhir3127 » Mon Aug 25, 2008 12:23 am
gmattester wrote:Can someone plz. explain this problem
I go with B..

statement 1.X#3 doesnt give any picture ..suppose x = 4

rt(4-3)^2 # 3-4
1 is not equal to -1...................hence in sufficient

statement 2.

-X(ABS (x)) >0 we know from this that X<0 only then the equation will be >0

now for any negative value of X the equation
rt ( X-3)^2 = 3-X

hence B

hope that helps
Top
Junior | Next Rank: 30 Posts
Posts: 14
Joined: Fri Aug 22, 2008 9:51 pm
Thanked: 3 times

by carefreeamit » Mon Aug 25, 2008 12:23 am
statement 1 is not sufficient
statement 2 -
-x|x|> 0
since |x| is positive -x should also be positive i.e. x is negative.
take any negative value of x and substitute.

Ans B
Top
Master | Next Rank: 500 Posts
Posts: 229
Joined: Thu Nov 08, 2007 3:47 pm
Thanked: 14 times
GMAT Score:750

by LSB » Mon Aug 25, 2008 2:19 am
rt ( X-3)^2 = 3-X (square and multiply)
X^2-6x+9 = 9-6X+X^2
2X^2 = 0
This essentially asks if X=0

1) X <>3 INSUFF ... X could be anything but 3
2) From this it follows X>0.
If X>0, then 2X^2 cannot be zero
Top
Legendary Member
Posts: 891
Joined: Sat Aug 16, 2008 4:21 am
Thanked: 27 times
Followed by:1 members
GMAT Score:660(

by 4meonly » Mon Aug 25, 2008 8:38 am
LSB wrote: X^2-6x+9 = 9-6X+X^2
2X^2 = 0
X^2-6x+9 = 9-6X+X^2
is the same X^2-6x+9 = X^2-6X+9

how i've got?

i missed something?

2X^2 = 0
Top
Newbie | Next Rank: 10 Posts
Posts: 1
Joined: Wed Aug 06, 2008 1:22 pm

by chisbri » Mon Aug 25, 2008 8:59 am
I tried to solve this by squaring both sides:

(x-3)^2 = (3-x)^2

In which case, the statement would be valid for all values of X. What have I done wrong here?[/img]
Top
Master | Next Rank: 500 Posts
Posts: 229
Joined: Thu Nov 08, 2007 3:47 pm
Thanked: 14 times
GMAT Score:750

by LSB » Mon Aug 25, 2008 12:11 pm
You're right. Typo on my end (it was late at night). Funny how I still got it right :-) .

It's a tough one because if we do square like I suggested then we get rid of the positive vs negative contraint. I guess the only way I can see is to plug numbers into the original equation then.
Top
Post new topic Post Reply
• Page 1 of 1