GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 23 Sep 2018, 16:58

Close

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Line C is a straight line in the coordinate geometry plane defined by

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 49320
Line C is a straight line in the coordinate geometry plane defined by  [#permalink]

Show Tags

New post 06 Jun 2017, 10:31
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

64% (00:49) correct 36% (00:51) wrong based on 128 sessions

HideShow timer Statistics

Line C is a straight line in the coordinate geometry plane defined by the equation y=ax+b, for which a and b are constants. What is the value of a?

(1) Line C is perpendicular to a line with the equation y=−2x+5
(2) Line C is parallel to a line with the equation y=(1−a)x+b+2

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Manager
Manager
avatar
B
Status: Preparing
Joined: 05 May 2016
Posts: 58
Location: India
Concentration: International Business, Finance
Re: Line C is a straight line in the coordinate geometry plane defined by  [#permalink]

Show Tags

New post 06 Jun 2017, 11:10
Bunuel wrote:
Line C is a straight line in the coordinate geometry plane defined by the equation y=ax+b, for which a and b are constants. What is the value of a?

(1) Line C is perpendicular to a line with the equation y=−2x+5
(2) Line C is parallel to a line with the equation y=(1−a)x+b+2



I think the answer should be D.
Statement 1 gives a which is slope as 1/2.
Statement also gives a which is slope as 1/2. a=1-a, so a =1/2
Director
Director
avatar
S
Joined: 21 Mar 2016
Posts: 531
Reviews Badge
Re: Line C is a straight line in the coordinate geometry plane defined by  [#permalink]

Show Tags

New post 08 Jun 2017, 09:16
Bunuel wrote:
Line C is a straight line in the coordinate geometry plane defined by the equation y=ax+b, for which a and b are constants. What is the value of a?

(1) Line C is perpendicular to a line with the equation y=−2x+5
(2) Line C is parallel to a line with the equation y=(1−a)x+b+2



stat 1 : perpendicular lines have slope as m1 * m2 = -1
so slope can be calculated from this..

stat2: parallel line have same slope,,,hence suff

ans D
SVP
SVP
User avatar
P
Joined: 08 Jul 2010
Posts: 2334
Location: India
GMAT: INSIGHT
WE: Education (Education)
Reviews Badge
Re: Line C is a straight line in the coordinate geometry plane defined by  [#permalink]

Show Tags

New post 08 Jun 2017, 20:15
Bunuel wrote:
Line C is a straight line in the coordinate geometry plane defined by the equation y=ax+b, for which a and b are constants. What is the value of a?

(1) Line C is perpendicular to a line with the equation y=−2x+5
(2) Line C is parallel to a line with the equation y=(1−a)x+b+2


Question: What is the value of a = What is the slope of line?

Statement 1: Line C is perpendicular to a line with the equation y=−2x+5
Perpendicular lines have relation of slopes as \(m_1*m_2 = -1\)
i.e. a*(-2) = -1
i.e. a = 1/2
SUFFICIENT

Statement 2: Line C is parallel to a line with the equation y=(1−a)x+b+2
Parallel lines have relation of slopes as \(m_1 = m_2\)
i.e. a = (1-a)
i.e. a = 1/2
SUFFICIENT

Answer: option D
_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Director
Director
avatar
S
Joined: 12 Nov 2016
Posts: 759
Location: United States
Schools: Yale '18
GMAT 1: 650 Q43 V37
GRE 1: Q157 V158
GPA: 2.66
Re: Line C is a straight line in the coordinate geometry plane defined by  [#permalink]

Show Tags

New post 17 Jun 2017, 10:15
Bunuel wrote:
Line C is a straight line in the coordinate geometry plane defined by the equation y=ax+b, for which a and b are constants. What is the value of a?

(1) Line C is perpendicular to a line with the equation y=−2x+5
(2) Line C is parallel to a line with the equation y=(1−a)x+b+2



We can apply simple algebra to solve this question

Statement 1
Because we have the slope of a perpendicular line we of course can know the slope of the other line- just the negative reciprocal

Suff

Statement 2

This line is parallel- the 2 added to the end doesn't really mean anything- ignore it- algebraic the important thing in this question

(1-a)x= ax
1-a=a
1= 2a
a= 1/2

Thus
"D"
Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 8160
Premium Member
Re: Line C is a straight line in the coordinate geometry plane defined by  [#permalink]

Show Tags

New post 29 Jun 2018, 00:00
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

GMAT Club Bot
Re: Line C is a straight line in the coordinate geometry plane defined by &nbs [#permalink] 29 Jun 2018, 00:00
Display posts from previous: Sort by

Line C is a straight line in the coordinate geometry plane defined by

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Events & Promotions

PREV
NEXT


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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®.