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

 It is currently 07 Jul 2015, 18:26

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

Line L passes through point (1,4), and the product of its

Author Message
TAGS:
Director
Joined: 24 Oct 2005
Posts: 575
Location: NYC
Followers: 1

Kudos [?]: 26 [0], given: 0

Line L passes through point (1,4), and the product of its [#permalink]  19 Mar 2006, 13:08
00:00

Difficulty:

(N/A)

Question Stats:

50% (02:26) correct 50% (00:39) wrong based on 1 sessions
--------------------------------------------------------------------------------

Line L passes through point (1,4), and the product of its intercepts with axis-x and axis-y is negative. Which of the following point is on the line L?

A. (2,3)
B. (5,7)
C. (4,2)
D. (4,-1)
E. (5, -1)
_________________

Success is my only option, failure is not -- Eminem

Manager
Joined: 20 Feb 2006
Posts: 213
Followers: 1

Kudos [?]: 5 [0], given: 0

B (5,7)
We can deduce from the conditions in the question that slope of the line > 0. From there onwards, it is POE.
Director
Joined: 24 Oct 2005
Posts: 575
Location: NYC
Followers: 1

Kudos [?]: 26 [0], given: 0

I do understand that B leads to a positive slope.. but what I dont understand is why we need a positive slope?? because the product of the intecepts is negative?
_________________

Success is my only option, failure is not -- Eminem

Manager
Joined: 20 Feb 2006
Posts: 213
Followers: 1

Kudos [?]: 5 [0], given: 0

Yes...
Let us take the equation of the line to be y = mx + c. (We do not know the nature of the numbers yet).
x-intercept (when y = 0) = -c/m
y-intercept (when x = 0) = c
Product of intercepts = -(c^2)/m < 0 as per the question.
=> m < 0 since c^2 is always positive.
Hope this helps.
VP
Joined: 21 Sep 2003
Posts: 1065
Location: USA
Followers: 3

Kudos [?]: 40 [0], given: 0

chuckle wrote:
Yes...
Let us take the equation of the line to be y = mx + c. (We do not know the nature of the numbers yet).
x-intercept (when y = 0) = -c/m
y-intercept (when x = 0) = c
Product of intercepts = -(c^2)/m < 0 as per the question.
=> m < 0 since c^2 is always positive.
Hope this helps.

Going by your logic, Only C has -ve slope (= -2/3). So C should be the answer.
_________________

"To dream anything that you want to dream, that is the beauty of the human mind. To do anything that you want to do, that is the strength of the human will. To trust yourself, to test your limits, that is the courage to succeed."

- Bernard Edmonds

Manager
Joined: 20 Feb 2006
Posts: 213
Followers: 1

Kudos [?]: 5 [0], given: 0

Sorry giddi...
I made a mistake. m should be > 0.
Also, all the answer choices except B give negative slope...
VP
Joined: 21 Sep 2003
Posts: 1065
Location: USA
Followers: 3

Kudos [?]: 40 [0], given: 0

chuckle wrote:
Sorry giddi...
I made a mistake. m should be > 0.
Also, all the answer choices except B give negative slope...

Thanks! I also missed the -ve sign

And no need for sorry pal. Your solution is really neat
_________________

"To dream anything that you want to dream, that is the beauty of the human mind. To do anything that you want to do, that is the strength of the human will. To trust yourself, to test your limits, that is the courage to succeed."

- Bernard Edmonds

SVP
Joined: 14 Dec 2004
Posts: 1706
Followers: 1

Kudos [?]: 59 [0], given: 0

Yes, indeed very neat solution

My approach to this problem was slightly different.

I visualized the line , if product of y intercept & x intercept is < 0,
it means the line cuts the in such a way that the slope is > 0.

Only (5,7) satisfies the requirement!
Attachments

File comment: Line Graph

graph.JPG [ 3.36 KiB | Viewed 689 times ]

Manager
Joined: 23 Jan 2006
Posts: 192
Followers: 1

Kudos [?]: 12 [0], given: 0

Re: PS + Coordinate geometry [#permalink]  20 Mar 2006, 11:56
bewakoof wrote:
Line L passes through point (1,4), and the product of its intercepts with axis-x and axis-y is negative. Which of the following point is on the line L?

A. (2,3)
B. (5,7)
C. (4,2)
D. (4,-1)
E. (5, -1)

Correct me if I am wrong, but shouldn't the question be worded:
"Which of the following points could be on the line L?"

Good question, nonetheless. Where is it from?
Manager
Joined: 09 Feb 2006
Posts: 91
Location: Prague, CZ
Followers: 1

Kudos [?]: 21 [0], given: 0

It's obvious when you make a drawing. Line L can be only in the direction of red lines (y+, x- or y-, x+). The only point that meets the criteria is point B ... green line is line L.
Attachments

graph.gif [ 4.03 KiB | Viewed 662 times ]

Intern
Joined: 18 Jan 2006
Posts: 15
Followers: 0

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

general eqn of the line:
x/a+y/b=1.
m = -a/b
we have ab < 0.
so m>0,

therefore, angle made at the x axis is acute.
only (B) does that.

Thanks,
_________________

If I cant win, I'll die flying

Director
Joined: 24 Oct 2005
Posts: 575
Location: NYC
Followers: 1

Kudos [?]: 26 [0], given: 0

Re: PS + Coordinate geometry [#permalink]  21 Mar 2006, 18:21
kook44 wrote:
bewakoof wrote:
Line L passes through point (1,4), and the product of its intercepts with axis-x and axis-y is negative. Which of the following point is on the line L?

A. (2,3)
B. (5,7)
C. (4,2)
D. (4,-1)
E. (5, -1)

Correct me if I am wrong, but shouldn't the question be worded:
"Which of the following points could be on the line L?"

Good question, nonetheless. Where is it from?

i got this question from some other forum.. I dont remember, from where..
_________________

Success is my only option, failure is not -- Eminem

Re: PS + Coordinate geometry   [#permalink] 21 Mar 2006, 18:21
Similar topics Replies Last post
Similar
Topics:
2 In a rectangular coordinate system, if a line passes through the point 2 23 Oct 2014, 00:17
5 Line D passes through point (-2,5), and the product of its x-intercept 7 12 Apr 2011, 21:43
3 If line L passes through 4 31 Mar 2011, 04:45
2 Line L passes through (5,0) and (0,10).If a point is 4 10 Mar 2008, 08:45
Display posts from previous: Sort by