• NEW! FREE Beat The GMAT Quizzes
Hundreds of Questions Highly Detailed Reporting Expert Explanations
• 7 CATs FREE!
If you earn 100 Forum Points

Engage in the Beat The GMAT forums to earn
100 points for $49 worth of Veritas practice GMATs FREE VERITAS PRACTICE GMAT EXAMS Earn 10 Points Per Post Earn 10 Points Per Thanks Earn 10 Points Per Upvote ## equations ##### This topic has 4 member replies ## equations Is y = 6? 1. y^2 = 36 2. y^2- 7y + 6 = 0 Legendary Member Joined 08 Jul 2008 Posted: 661 messages Upvotes: 48 Is y = 6? 1. y^2 = 36 You have either y=6 or y=-6 So it is insufficient. 2. y^2- 7y + 6 = 0 We can write it like that (y-6)(y-1)=0 So here the solutions are either y=6 or y=1 So it is insufficient. 1 and 2. y=6 or y=-6 and y=6 or y=1 So it is 6 ! C Master | Next Rank: 500 Posts Joined 22 Apr 2008 Posted: 301 messages Upvotes: 2 This is exactly what I had: y=6 or y=-6 and y=6 or y=1. However, I chose E since y could be +/-6 or 1. This is an elementary question, but are we supposed to pick the common value 6 in such scenarios? Legendary Member Joined 08 Jul 2008 Posted: 661 messages Upvotes: 48 In this case, you cannot chose y=1 or y=-6 You can see that for y=1, y^2 is different from 36 for y=-6, y^2- 7y + 6 is different from 0 But with y=6 we have y^2 = 36 and y^2- 7y + 6 = 0 What you look is a solution which suits both statements, your solution cannot contradict with one equation but be wrong with another equation. You should practice DS questions to be used to what they ask you. Master | Next Rank: 500 Posts Joined 22 Apr 2008 Posted: 301 messages Upvotes: 2 Thanks pepeprepa. You cleared my doubt. Later! • Free Practice Test & Review How would you score if you took the GMAT Available with Beat the GMAT members only code • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • Award-winning private GMAT tutoring Register now and save up to$200

Available with Beat the GMAT members only code

• 5-Day Free Trial
5-day free, full-access trial TTP Quant

Available with Beat the GMAT members only code

• Free Trial & Practice Exam
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• Get 300+ Practice Questions
25 Video lessons and 6 Webinars for FREE

Available with Beat the GMAT members only code

• Magoosh
Study with Magoosh GMAT prep

Available with Beat the GMAT members only code

• 1 Hour Free
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• 5 Day FREE Trial
Study Smarter, Not Harder

Available with Beat the GMAT members only code

• FREE GMAT Exam
Know how you'd score today for \$0

Available with Beat the GMAT members only code

### Top First Responders*

1 Ian Stewart 53 first replies
2 Brent@GMATPrepNow 36 first replies
3 Jay@ManhattanReview 29 first replies
4 GMATGuruNY 25 first replies
5 ceilidh.erickson 15 first replies
* Only counts replies to topics started in last 30 days
See More Top Beat The GMAT Members

### Most Active Experts

1 Scott@TargetTestPrep

Target Test Prep

199 posts
2 Max@Math Revolution

Math Revolution

90 posts
3 Brent@GMATPrepNow

GMAT Prep Now Teacher

76 posts
4 Ian Stewart

GMATiX Teacher

62 posts
5 GMATGuruNY

The Princeton Review Teacher

44 posts
See More Top Beat The GMAT Experts