It is currently 19 Oct 2017, 04:39

### 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 xy>0

Author Message
Retired Moderator
Joined: 18 Jul 2008
Posts: 960

Kudos [?]: 294 [0], given: 5

### Show Tags

02 Dec 2008, 09:17
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Is xy>0

(1) x - y > - 2
(2) x - 2y < - 6

GUys, what's the easiest way to do this? I plugged in numbers and it started to get confusing, and blew past the 2 minutes.

Kudos [?]: 294 [0], given: 5

Manager
Joined: 02 Nov 2008
Posts: 58

Kudos [?]: 2 [0], given: 0

### Show Tags

02 Dec 2008, 09:26
I get c

I subtract eq 2 from 1 and

Kudos [?]: 2 [0], given: 0

Manager
Joined: 14 Oct 2008
Posts: 160

Kudos [?]: 64 [0], given: 0

### Show Tags

02 Dec 2008, 09:38
IMO C.

From 1st equation
x > y-2 ( not sufficient )

From 2nd equation
x < 2y-6 ( not sufficient)

Combining :
(y-2) < x < (2y-6)

hence y-2 < 2y-6
y > 4

Substituting the value in 1st equations we see that x.y is always positive

we can also check by substituting values in equation (y-2) < x < (2y-6)

Hence C.

Kudos [?]: 64 [0], given: 0

Retired Moderator
Joined: 18 Jul 2008
Posts: 960

Kudos [?]: 294 [0], given: 5

### Show Tags

02 Dec 2008, 11:35
But to solve for A and also B independently, you guys plugged in numbers?

Kudos [?]: 294 [0], given: 5

SVP
Joined: 17 Jun 2008
Posts: 1534

Kudos [?]: 279 [0], given: 0

### Show Tags

02 Dec 2008, 12:27
Alternatively, draw the graph of the two inequalities and find out the common area. The common area will be in quadrant A and hence xy > 0 only when both the inequalities are considered.

Kudos [?]: 279 [0], given: 0

Manager
Joined: 14 Oct 2008
Posts: 160

Kudos [?]: 64 [0], given: 0

### Show Tags

02 Dec 2008, 17:00
But to solve for A and also B independently, you guys plugged in numbers?

Yes I had plugged in numbers individually in both statements .....

Kudos [?]: 64 [0], given: 0

Senior Manager
Joined: 05 Jun 2008
Posts: 304

Kudos [?]: 181 [0], given: 0

### Show Tags

03 Dec 2008, 06:46
Is xy>0

(1) x - y > - 2
(2) x - 2y < - 6

GUys, what's the easiest way to do this? I plugged in numbers and it started to get confusing, and blew past the 2 minutes.

Stem 1 -Insuff
Stemm 2 - InSuff
Both Put together are suff, Lts see
After Subst 2 from 1
x - y -x + 2y > - 2 + 6
y> 4 after puting this value in 1
X>2, which means XY>8

Kudos [?]: 181 [0], given: 0

Re: Is xy>0   [#permalink] 03 Dec 2008, 06:46
Display posts from previous: Sort by