Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 20 Aug 2014, 08:59

# Flash Sale:

The Economist GMAT Tutor - 15% Off All Courses

### 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

# Lines a and b have different y-intercepts. When line a is

Author Message
TAGS:
Manager
Joined: 18 Jun 2011
Posts: 58
Followers: 1

Kudos [?]: 50 [0], given: 0

Lines a and b have different y-intercepts. When line a is [#permalink]  19 Jun 2011, 07:04
00:00

Difficulty:

45% (medium)

Question Stats:

46% (02:05) correct 54% (01:09) wrong based on 35 sessions
Lines a and b have different y-intercepts. When line a is reflected around the y-axis, is its reflection parallel to line b?

(1) Line a is perpendicular to line b.

(2) The slope of line b > 0.
[Reveal] Spoiler: OA
Current Student
Joined: 26 May 2005
Posts: 571
Followers: 18

Kudos [?]: 104 [1] , given: 13

Re: Coordinate Geometry Problem [#permalink]  19 Jun 2011, 08:54
1
KUDOS
guygmat wrote:
Lines a and b have different y-intercepts. When line a is reflected around the y-axis, is its reflection parallel to line b?

(1) Line a is perpendicular to line b.

(2) The slope of line b > 0.

line a = y =mx+b
line b = y = nx+c

now in case a line reflects, its slope changes sign and Y intercept remains same
so relected a = y= -mx+b

now the question asks is -m =n ( parallel lines will have same slope)

st1. -m*n = -1
m = 1 and n = 1 ... satisfies our condition
m = 1/3 and n = 3 ; -m*n = -1 but -m is not equal to n ... hence in sufficient

st2: n>0
same as above... insufficient

1&2
m = 1 n =1 ok
m = 1/3 and n = 3 not ok

hence E
Re: Coordinate Geometry Problem   [#permalink] 19 Jun 2011, 08:54
Similar topics Replies Last post
Similar
Topics:
3 In the xy-plane, line a and line b have the same slope. 3 24 Apr 2012, 19:54
6 Lines a and b have different y-intercepts. When line a is 19 20 Mar 2011, 16:15
If two lines have slopes a and b , respectively, are they 3 15 May 2010, 10:41
34 In the xy-plane, what is the y-intercept of line l? 12 28 Feb 2010, 19:51
The y-intercept of a line l is 4. If the slope of l is 3 17 Sep 2006, 16:10
Display posts from previous: Sort by