Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions

variables

Expert replies
by naaga » Mon Feb 23, 2009 2:38 am
. If x ≠ 1, is y equal to x + 1?

(1) y-2/x-1 = 0

(2) y^2 = (x + 1)^2


folks I got the answer D

but the OA is A

can anyone explain
Last edited by naaga on Mon Feb 23, 2009 4:11 am, edited 1 time in total.
Join the discussion
Source: — Data Sufficiency |

by DanaJ » Mon Feb 23, 2009 2:52 am
The equation in stmt 1 is fulfilled only if y-2 = 0, giving us y = 2. This does not help regarding the relationship between x and y, so 1 is insufficient.
The second equation helps establish that y = x + 1 or that y = -(x + 1). Since we cannot tell which case it really is, then this stmt is insufficient as well.

Put the two together and you get two cases from stmt 2:
a. y = x + 1 = 2 makes x = 1, which does not fit with the initial constraint that x is not 1
b. y = -(x + 1) = 2, making x = -1, which does fit with x being different from 1.

So I'd go with C.... Maybe I'm missing smth over here, I get a completely different answer....
Join the discussion

by bluementor » Mon Feb 23, 2009 3:04 am
DanaJ wrote:The equation in stmt 1 is fulfilled only if y-2 = 0, giving us y = 2. This does not help regarding the relationship between x and y, so 1 is insufficient.
But we know that x is not equal to 1, and if y = 2, y will never be equal to x + 1. Isn't this sufficient to answer the question stem?

-BM-
Join the discussion

by naaga » Mon Feb 23, 2009 4:17 am
the answer A satisfies the equation,

( y-2 )/ (x -1 ) = 0

Y = 2 , obviously x doesn't equal to 1, with statement we can answer.

why B cannot satisfies the equation ?
Join the discussion

Re: variables

by sureshbala » Mon Feb 23, 2009 5:24 am
naaga wrote:. If x ≠ 1, is y equal to x + 1?

(1) y-2/x-1 = 0

(2) y^2 = (x + 1)^2


folks I got the answer D

but the OA is A

can anyone explain
Statement I alone is sufficient....

Look at this....

Given that y-2/x-1 = 0.

So y-2 =0 , i.e y =2.

Now, since y=2, y will be equal x+1 provided x=1. But in the statement it is clearly mentioned that x is not equal to 1. So x+1 is not equal to 2, where as y=2. So we can conclude that y is not equal to x+1.

Hence I is sufficient.

Coming to statement II, since y^2 = (x+!)^2, we have y= (x+1) or -(x+1). So II is not sufficient.

Hence A
Join the discussion

by DanaJ » Mon Feb 23, 2009 6:06 am
bluementor: you are so right... Your answer actually made me laugh because it was so plain and simple, while I'm over here solving zounds of equations... :))
Join the discussion