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

Redeem

Confused on the graph of this

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |

GMAT/MBA Expert

User avatar
Elite Legendary Member
Posts: 10392
Joined: Sun Jun 23, 2013 6:38 pm
Location: Palo Alto, CA
Thanked: 2867 times
Followed by:511 members
GMAT Score:800

by [email protected] » Thu Aug 08, 2013 11:04 pm
Hi shibsriz,

Based on some prior discussions that I've read and some ideas that have been floated around in this forum lately, I'm going to offer some suggestions/hints and let you retry this question on your own. The full explanation will come later.

1) Draw a graph of the 2 points that you have (point B and C).
2) To assess Fact 1, sketch some possible lines that COULD occur based on this info (COULD 0,0 be in the triangle? Could it not?)
3) To assess Fact 2, sketch some possible lines that COULD occur based on this info (COULD 0,0 be in the triangle? Could it not?)
4) Combine, if necessary.

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Top
Master | Next Rank: 500 Posts
Posts: 429
Joined: Wed Sep 19, 2012 11:38 pm
Thanked: 6 times
Followed by:4 members

by [email protected] » Fri Aug 09, 2013 5:22 am
[email protected] wrote:The vertices of a triangle are on points A(a,b), B(2,2), C(2,-2). Is the origin (0,0) bounded by the sides of the triangle?

(1) The slope of the line AB is positive and the slope of the line AC positive
(2) b is negative
What I understand is that both the statements have infinite solutions to it is it right?
Top
GMAT Instructor
Posts: 2630
Joined: Wed Sep 12, 2012 3:32 pm
Location: East Bay all the way
Thanked: 625 times
Followed by:119 members
GMAT Score:780

by Matt@VeritasPrep » Fri Aug 09, 2013 9:40 am
Well, sort of - there aren't infinite solutions to the problem as written (only "Yes", "No", and "Maybe"), but there may be an infinite number of values of (a,b).

I'd try drawing a few triangles that satisfy one (or both) statements and seeing what happens: do you always get (0,0) in the triangle, do you never, or does it only happen sometimes?

For example, are both of these triangles acceptable, given the two statements?


Image
Top

GMAT/MBA Expert

User avatar
Elite Legendary Member
Posts: 10392
Joined: Sun Jun 23, 2013 6:38 pm
Location: Palo Alto, CA
Thanked: 2867 times
Followed by:511 members
GMAT Score:800

by [email protected] » Fri Aug 09, 2013 6:58 pm
Hi shibsriz,

We can use Matt's sketch since it's already in the thread.

With the information in Fact 1, you could draw the two triangles that appear in the graph. One of them contains point (0,0) which would gives us a YES answer; one them does NOT contain the point (0,0) which would gives us a NO answer. So, Fact 1 is INSUFFICIENT.

Those same two examples would fit the information in Fact 2, so we'd have a YES and NO. Fact 2 is also INSUFFICIENT.

Combining Facts, we have the same two examples for each, with the same answers (one YES, one NO), so in the end...

Final Answer: E

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
Image
Top
Post new topic Post Reply
• Page 1 of 1