BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

OG-12.94

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 138
Joined: Mon Mar 14, 2011 8:24 pm
Thanked: 1 times

OG-12.94

by rishijhawar » Wed Jul 06, 2011 11:29 pm
If Line K in th xy-plane has equation y=mx+b, where m and b are constants, what is the slope of k?
1) K is parallel to the line with equation y = (1-m)x + b + 1
2) K intersects the line with equation y=2x+3 at the point (2,7))
[spoiler]OA A. Though I understood why B is insufficient, will option B be sufficient if the question is reworded that K and y=2x+3 are perpendicular (and hence we know from K's slope the relation m1*m2=-1).
Also, which other additional/new info will make B sufficient. Thx [/spoiler]
Top
Source: — Data Sufficiency |
User avatar
Senior | Next Rank: 100 Posts
Posts: 54
Joined: Sun Nov 29, 2009 7:11 pm
Location: Bangalore
Thanked: 4 times

by abhisays » Thu Jul 07, 2011 12:38 am
From 1 we have m = 1-m hence m = 1/2 So 1 is sufficient.

From 2 we have mx+b = 2x+3 i.e 2m +b = 7, we have only this equation, so 2 is not sufficient.

Hence Answer should be A
Top
User avatar
Senior | Next Rank: 100 Posts
Posts: 90
Joined: Fri Jan 22, 2010 1:10 pm
Location: New Jersey
Thanked: 13 times
Followed by:4 members
GMAT Score:640

by Mom4MBA » Thu Jul 07, 2011 1:58 am
if the question is reworded that K and y=2x+3 are perpendicular (and hence we know from K's slope the relation m1*m2=-1).
Also, which other additional/new info will make B sufficient.
you are right, had it been given that the line is perpendicular to y=2x+3, then even statement 2 would have been sufficient.
Statement 2 would also have been sufficient if one point on line K was also given.
Stay focused
Top
Post new topic Post Reply
• Page 1 of 1