It is currently 13 Dec 2017, 18:43

# Decision(s) Day!:

CHAT Rooms | Ross R1 | Kellogg R1 | Darden R1 | Tepper R1

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# y = x^2 + 6x 7, x= 1). x is positive integer 2). y^2=y

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
Manager
Joined: 03 Jul 2006
Posts: 173

Kudos [?]: 37 [0], given: 0

y = x^2 + 6x 7, x= 1). x is positive integer 2). y^2=y [#permalink]

### Show Tags

12 Sep 2006, 18:50
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

y = x^2 + 6x – 7, x=

1). x is positive integer

2). y^2=y

Kudos [?]: 37 [0], given: 0

Manager
Joined: 03 Jul 2006
Posts: 173

Kudos [?]: 37 [0], given: 0

### Show Tags

12 Sep 2006, 19:11
why not 'A'

from the stem, x = -7 or 1

and A says x has to be +ve then x must be 1 ?

Kudos [?]: 37 [0], given: 0

VP
Joined: 28 Mar 2006
Posts: 1367

Kudos [?]: 38 [0], given: 0

### Show Tags

12 Sep 2006, 19:14
rkatl wrote:
why not 'A'

from the stem, x = -7 or 1

and A says x has to be +ve then x must be 1 ?

here the eq is not =0 but equal to y.

How can you deduce anything from 1 only?

either it has to be C or E

Kudos [?]: 38 [0], given: 0

CEO
Joined: 20 Nov 2005
Posts: 2892

Kudos [?]: 337 [0], given: 0

Schools: Completed at SAID BUSINESS SCHOOL, OXFORD - Class of 2008

### Show Tags

12 Sep 2006, 20:25
C

St1: clearly INSUFF

St2: y = 0 or y = 1.
then there are two equations
x^2 + 6x-7 = 0 gives us x = 1 or -7 and
x^2+6x-8 = 0 gives us two non-integer roots.: INSUFF

Together:
x = 1.: SUFF
_________________

SAID BUSINESS SCHOOL, OXFORD - MBA CLASS OF 2008

Kudos [?]: 337 [0], given: 0

Retired Moderator
Joined: 05 Jul 2006
Posts: 1748

Kudos [?]: 447 [0], given: 49

### Show Tags

12 Sep 2006, 23:27
the key here is statment b

y^2 =y thus y is either = {-1,1,0}....insuff

both together

x is positive and y = x^2 + 6x â€“ 7

if y = -1 thus x^2 + 6x-6 = 0....this equation has two non intiger answers one +ve and one -ve ( test with (b^2 - 4ac)....insuff

y = 1 thus x^2 + 6x-8 = 0 this equation has non intiger answers one +ve and one -ve....insuff

if y = 0 the equation has two intiger roots and as it is mentioned in one that x is positive intiger

thus C is my answer

Kudos [?]: 447 [0], given: 49

12 Sep 2006, 23:27
Display posts from previous: Sort by

# y = x^2 + 6x 7, x= 1). x is positive integer 2). y^2=y

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 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®.