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

It is currently 24 Nov 2014, 17:54

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

In the xy-plane is the slope of line k equal to 0?

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Director
Director
avatar
Joined: 29 Nov 2012
Posts: 928
Followers: 12

Kudos [?]: 338 [0], given: 543

In the xy-plane is the slope of line k equal to 0? [#permalink] New post 20 Jan 2013, 06:09
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  95% (hard)

Question Stats:

18% (01:35) correct 82% (00:36) wrong based on 236 sessions
In the xy-plane is the slope of line k equal to 0?

(1) The x-intercept of k is 0.
(2) The y-intercept of k is 0.
[Reveal] Spoiler: OA

_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios gmat-prep-software-analysis-and-what-if-scenarios-146146.html


Last edited by fozzzy on 18 Jun 2013, 00:37, edited 1 time in total.
Expert Post
3 KUDOS received
Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Status: Preparing for the another shot...!
Joined: 03 Feb 2011
Posts: 1425
Location: India
Concentration: Finance, Marketing
GPA: 3.75
Followers: 133

Kudos [?]: 670 [3] , given: 62

GMAT ToolKit User Premium Member
Re: In the xy-plance is the slope of line k equal to 0? [#permalink] New post 20 Jan 2013, 07:25
3
This post received
KUDOS
Expert's post
fozzzy wrote:
In the xy-plance is the slope of line k equal to 0?

1) the x-intercept of k is 0
2) the y-intercept of k is 0.


The question is asking whether the link k is parallel to x-axis or x-axis itself.

1) x intercept of k =0
i.e. when line k intersects x axis, the intersection point is at 0 distance from origin OR indirectly the line k intersects x axis at origin.
Insufficient infromation as the line can have any slope.

2) y intercept of k=0
i.e. when line k intersects y axis, the intersection point is at 0 distance from origin OR indirectly the line k intersects y axis at origin.
Insufficient info as the line can have any slope.

On combining, we see that the line passes through origin.
Now we see that the line can have any slope. The slope can be positive, negative and zero.
Not sufficient.
_________________

Prepositional Phrases Clarified|Elimination of BEING| Absolute Phrases Clarified
Rules For Posting
www.Univ-Scholarships.com

2 KUDOS received
Director
Director
avatar
Joined: 29 Nov 2012
Posts: 928
Followers: 12

Kudos [?]: 338 [2] , given: 543

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 21 Jan 2013, 04:13
2
This post received
KUDOS
Here is a screenshot of the question
Attachments

question screenshot.jpg
question screenshot.jpg [ 14.31 KiB | Viewed 4494 times ]


_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios gmat-prep-software-analysis-and-what-if-scenarios-146146.html

1 KUDOS received
Intern
Intern
avatar
Joined: 07 Sep 2013
Posts: 1
Followers: 0

Kudos [?]: 1 [1] , given: 0

Re: In the xy-plance is the slope of line k equal to 0? [#permalink] New post 07 Sep 2013, 13:25
1
This post received
KUDOS
Marcab wrote:
fozzzy wrote:
In the xy-plance is the slope of line k equal to 0?

1) the x-intercept of k is 0
2) the y-intercept of k is 0.


The question is asking whether the link k is parallel to x-axis or x-axis itself.

1) x intercept of k =0
i.e. when line k intersects x axis, the intersection point is at 0 distance from origin OR indirectly the line k intersects x axis at origin.
Insufficient infromation as the line can have any slope.

2) y intercept of k=0
i.e. when line k intersects y axis, the intersection point is at 0 distance from origin OR indirectly the line k intersects y axis at origin.
Insufficient info as the line can have any slope.

On combining, we see that the line passes through origin.
Now we see that the line can have any slope. The slope can be positive, negative and zero.
Not sufficient.


Ok so I have a another solution, I would appreciate if I could get some comments.

1) x intercept of k =0
If you use y = mx + b, and you apply this condition, you get 0 = mx + b, which is the x intercept of K.
If you reorganize the elements, you get b/m = x. Then, m cannot be 0, because it would be undetermined.
So condition 1 is sufficient.

2) y intercept of k = 0
That just tells you b = 0, but it doesnt say anything about m.

Therefore A is correct.

Comments are appreciated.
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [1] , given: 3271

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 27 Sep 2013, 00:21
1
This post received
KUDOS
Expert's post
gmatter0913 wrote:
X-intercept of zero doesn't necessarily mean the line is horizontal, it could also mean that the line passes through origin.

Let us take a line passing through the points (2,2) and (0,0). (This line intersects the co-ordinate axes only at the origin)

The equation of the line is: y - 0 = (2-0)/(2-0) * (x-0)
This leads to the equation x=y

What is the x-intercept of this line? It is zero. Because it crosses the X-axis at 0.
What is the y-intercept of this line? It is zero. Because it crosses the Y-axis at 0.

What is the slope of this line? 45 degrees

A line can have a slope even if its X-intercept is zero. Because it passes through the origin.

The OA explanation says exactly that. If the X-intercept is zero, the line can be of the form y=x or y=0

Hence the answer is E


The OE is not correct.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Take a Survey about GMAT Prep - Win Prizes!

1 KUDOS received
Intern
Intern
avatar
Joined: 14 Dec 2013
Posts: 11
Followers: 0

Kudos [?]: 1 [1] , given: 5

GMAT ToolKit User
Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 28 Dec 2013, 23:46
1
This post received
KUDOS
fozzzy wrote:
In the xy-plane is the slope of line k equal to 0?

(1) The x-intercept of k is 0.
(2) The y-intercept of k is 0.


(1) x-intercept of a line is the distance of the origin from the point where the line cuts x-axis...x intercept 0 means the distance is 0, i.e. the line passes through the origin. You cannot say anything about the slope.

(2) y-intercept of a line is the distance of the origin from the point where the line cuts y-axis...y intercept 0 means the distance is 0, i.e. the line passes through the origin. Here also you cannot say anything about the slope

(1) and (2) both implies the same thing ( the line passes through origin)...you cannot say anything about the slope from both together. hence OA is correct answer is E
Expert Post
1 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [1] , given: 3271

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 01 Apr 2014, 07:21
1
This post received
KUDOS
Expert's post
goodyear2013 wrote:
Hi, I emailed the GMAC and checked the answer of this question.
I asked whether the answer could be (A).

Here is the reply of GMAC;

Answer is E.
The answer explanation explains it.
There are an infinite number of equations that have an x-intercept = 0 but do not have a slope equal to 0.

The answer explanation provides just one counter example: the equation y=x.
Other counterexamples include y=2x, y=3x, y=1/2x, y=1/3x, etc.
Because there is at least one example where the answer is yes (the slope = 0) and
at least one example where the answer is no (the slope is not = 0), then statement (1) is not sufficient.


None of the examples from GMAC (y=x, y=2x, y=3x, y=1/2x, y=1/3x) has the slope of 0. They say "an x-intercept = 0", while the question says "the x-intercept of k is 0". In the current form the answer must be A, no matter what the GMAC says.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Take a Survey about GMAT Prep - Win Prizes!

Director
Director
avatar
Joined: 29 Nov 2012
Posts: 928
Followers: 12

Kudos [?]: 338 [0], given: 543

Re: In the xy-plance is the slope of line k equal to 0? [#permalink] New post 21 Jan 2013, 03:50
Don't you think this question has ambiguity, the official explanation didn't really make sense. Its taking into account multiple intercepts.
_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios gmat-prep-software-analysis-and-what-if-scenarios-146146.html

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [0], given: 3271

Re: In the xy-plance is the slope of line k equal to 0? [#permalink] New post 21 Jan 2013, 04:04
Expert's post
fozzzy wrote:
Don't you think this question has ambiguity, the official explanation didn't really make sense.


Definitely. Is this question really from GMAT Prep? If so, can you pleas provide OA given there? Thank you.

In the xy-plane is the slope of line k equal to 0?

The questions basically asks whether line k is a horizontal line (the slope of any horizontal line is always zero. For more check here: math-coordinate-geometry-87652.html).

(1) The x-intercept of k is 0. Now, I'm not a verbal expert, but the x-intercept implies that there is only one point of interception with x-axis, which means that we can eliminate y=0 line. So, we have that line k is not y=0 and has x-intercept, thus it cannot be horizontal --> the slope does not equal to 0. Sufficient.

(2) The y-intercept of k is 0. Clearly insufficient.

Answer: A.

I think GMAT Prep is wrong here.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Take a Survey about GMAT Prep - Win Prizes!

Director
Director
avatar
Joined: 29 Nov 2012
Posts: 928
Followers: 12

Kudos [?]: 338 [0], given: 543

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 21 Jan 2013, 04:14
The official explanation
Attachments

Official explanation.jpg
Official explanation.jpg [ 21.43 KiB | Viewed 4483 times ]


_________________

Click +1 Kudos if my post helped...

Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/

GMAT Prep software What if scenarios gmat-prep-software-analysis-and-what-if-scenarios-146146.html

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [0], given: 3271

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 21 Jan 2013, 04:16
Expert's post
Manager
Manager
avatar
Joined: 11 Aug 2012
Posts: 136
Schools: HBS '16, Stanford '16
Followers: 0

Kudos [?]: 33 [0], given: 16

In the xy-plane, is the slope of line k equal to 0 ? [#permalink] New post 25 Apr 2013, 16:43
In the xy-plane, is the slope of line k equal to 0 ?

(1) The x-intercept of k is 0.
(2) The y-intercept of k is 0.

My doubt is this:
In (1), y = x satisfies the condition, and the answer would be NO.
But if we use y = 0, it seems that the answer would be YES. However, are we satisfying the condition? I am not sure.
If y=0, line k is touching every point of the x-axis because it is on the x axis. Therefore, there would be infinite x-intercepts, not only zero. In this sense, y=0 cannot be a solution, so the slope of line k is not 0. The answer would be NO.
So, (1) would be sufficient.
But the OA is E. :( Please explain.
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [0], given: 3271

Re: In the xy-plane, is the slope of line k equal to 0 ? [#permalink] New post 25 Apr 2013, 23:18
Expert's post
danzig wrote:
In the xy-plane, is the slope of line k equal to 0 ?

(1) The x-intercept of k is 0.
(2) The y-intercept of k is 0.

My doubt is this:
In (1), y = x satisfies the condition, and the answer would be NO.
But if we use y = 0, it seems that the answer would be YES. However, are we satisfying the condition? I am not sure.
If y=0, line k is touching every point of the x-axis because it is on the x axis. Therefore, there would be infinite x-intercepts, not only zero. In this sense, y=0 cannot be a solution, so the slope of line k is not 0. The answer would be NO.
So, (1) would be sufficient.
But the OA is E. :( Please explain.


Merging similar topics. Please refer to the solutions above.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Take a Survey about GMAT Prep - Win Prizes!

Intern
Intern
avatar
Joined: 01 Mar 2011
Posts: 11
Followers: 0

Kudos [?]: 1 [0], given: 25

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 27 Apr 2013, 09:42
I agree with marcab's solution. As rightly pointed out by marcab and GMat prep solution, a line passing through origin, y = x and say x axis,both have x and y intercept as zero. that is the reason why we write the equation of the point passing through origin as y =mx and not y = mx + c..I don;t think gmat prep solution or marcabs solution is wrong..
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [0], given: 3271

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 28 Apr 2013, 02:22
Expert's post
darsh wrote:
I agree with marcab's solution. As rightly pointed out by marcab and GMat prep solution, a line passing through origin, y = x and say x axis,both have x and y intercept as zero. that is the reason why we write the equation of the point passing through origin as y =mx and not y = mx + c..I don;t think gmat prep solution or marcabs solution is wrong..


This is a flawed question from GMAT Prep. The correct answer is A, not E.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Take a Survey about GMAT Prep - Win Prizes!

Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Status: Tomorrow will be a new day...
Joined: 22 Mar 2013
Posts: 957
Location: India
GPA: 3.51
WE: Information Technology (Computer Software)
Followers: 47

Kudos [?]: 463 [0], given: 213

Premium Member CAT Tests
Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 09 Sep 2013, 13:02
Let me give it a try:

In the xy-plane is the slope of line k equal to 0?
(1) The x-intercept of k is 0.
(2) The y-intercept of k is 0.

Y=MX + B standard equation. (check point; ok)

X intercept, theoretical knowledge : A single or multiple points on X axis where curve or line intersects X axis, i.e. at Y=0 for any X intercept.
(http://www.purplemath.com/modules/intrcept.htm)

Data given, X intercept as 0, means line is intersecting X axis at origin, as per above theoretical concept Y must be 0.

Therefore equation becomes.

0=m0+b ==> b=0, clearly we can see that X intercept is (0,0)

Equation of line becomes Y=MX

Now, here slope can take any value, thus we can not tell whether it is zero or not.

Further concept of infinite intercepts caused by overlap of any line over x axis is widely accepted, thus we can consider (0,0) as one of those infinite intercepts.

Answer should be E.

Kindly prove it graphically if you have any different concept.
_________________

Piyush K
-----------------------
Our greatest weakness lies in giving up. The most certain way to succeed is to try just one more time. ― Thomas A. Edison
Don't forget to press--> Kudos :)
My Articles: 1. WOULD: when to use? | 2. All GMATPrep RCs (New)
Tip: Before exam a week earlier don't forget to exhaust all gmatprep problems specially for "sentence correction".

Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [0], given: 3271

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 10 Sep 2013, 00:34
Expert's post
PiyushK wrote:
Let me give it a try:

In the xy-plane is the slope of line k equal to 0?
(1) The x-intercept of k is 0.
(2) The y-intercept of k is 0.

Y=MX + B standard equation. (check point; ok)

X intercept, theoretical knowledge : A single or multiple points on X axis where curve or line intersects X axis, i.e. at Y=0 for any X intercept.
(http://www.purplemath.com/modules/intrcept.htm)

Data given, X intercept as 0, means line is intersecting X axis at origin, as per above theoretical concept Y must be 0.

Therefore equation becomes.

0=m0+b ==> b=0, clearly we can see that X intercept is (0,0)

Equation of line becomes Y=MX

Now, here slope can take any value, thus we can not tell whether it is zero or not.

Further concept of infinite intercepts caused by overlap of any line over x axis is widely accepted, thus we can consider (0,0) as one of those infinite intercepts.

Answer should be E.

Kindly prove it graphically if you have any different concept.


THe correct answer is A, not E. Check here: in-the-xy-plane-is-the-slope-of-line-k-equal-to-146084.html#p1171693
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Take a Survey about GMAT Prep - Win Prizes!

Manager
Manager
avatar
Joined: 28 Jul 2013
Posts: 66
Location: India
Concentration: Marketing, Strategy
GPA: 3.62
WE: Engineering (Manufacturing)
Followers: 0

Kudos [?]: 12 [0], given: 23

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 10 Sep 2013, 03:33
Hi,

In my humble opinion the ans should be "e". The exp is not correctly explained.

slope of any line is given by dy/dx (change in y coordinate divided by change in x coordinate)

1) when x intercept is zero, that means y=0 or x=y in this case. So dy/dx = 0 as change in y coordinate is zero.

but in case of y=x; dy/dx = 1 (simple differentiation method) - Insufficient

2) when y intercept is zero that means, x=0 hence dy/dx = (dy/0) {infinite slope} similarly for y=x insufficient

Clearly both statement says the same thing x=0, x=y and y=0
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 24046
Followers: 3732

Kudos [?]: 31206 [0], given: 3271

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 10 Sep 2013, 04:36
Expert's post
sayansarkar wrote:
Hi,

In my humble opinion the ans should be "e". The exp is not correctly explained.

slope of any line is given by dy/dx (change in y coordinate divided by change in x coordinate)

1) when x intercept is zero, that means y=0 or x=y in this case. So dy/dx = 0 as change in y coordinate is zero.

but in case of y=x; dy/dx = 1 (simple differentiation method) - Insufficient

2) when y intercept is zero that means, x=0 hence dy/dx = (dy/0) {infinite slope} similarly for y=x insufficient

Clearly both statement says the same thing x=0, x=y and y=0


Not sure I understand what your reasoning but the correct answer is A. Check here: in-the-xy-plane-is-the-slope-of-line-k-equal-to-146084.html#p1171693
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Take a Survey about GMAT Prep - Win Prizes!

Senior Manager
Senior Manager
avatar
Joined: 12 Mar 2010
Posts: 385
Concentration: Marketing, Entrepreneurship
GMAT 1: 680 Q49 V34
Followers: 2

Kudos [?]: 40 [0], given: 87

Re: In the xy-plane is the slope of line k equal to 0? [#permalink] New post 27 Sep 2013, 00:20
X-intercept of zero doesn't necessarily mean the line is horizontal, it could also mean that the line passes through origin.

Let us take a line passing through the points (2,2) and (0,0). (This line intersects the co-ordinate axes only at the origin)

The equation of the line is: y - 0 = (2-0)/(2-0) * (x-0)
This leads to the equation x=y

What is the x-intercept of this line? It is zero. Because it crosses the X-axis at 0.
What is the y-intercept of this line? It is zero. Because it crosses the Y-axis at 0.

What is the slope of this line? 45 degrees

A line can have a slope even if its X-intercept is zero. Because it passes through the origin.

The OA explanation says exactly that. If the X-intercept is zero, the line can be of the form y=x or y=0

Hence the answer is E
Re: In the xy-plane is the slope of line k equal to 0?   [#permalink] 27 Sep 2013, 00:20
    Similar topics Author Replies Last post
Similar
Topics:
7 Experts publish their posts in the topic In the XY-Plane, is the slope of the line k equal to 0 ? voodoochild 9 08 Aug 2012, 08:18
4 Experts publish their posts in the topic In the xy-plane, if line k has negative slope, is the Bluelagoon 8 14 Mar 2012, 00:04
2 In the xy-plane, if line k has negative slope, is the skbjunior 3 15 Apr 2011, 19:19
Experts publish their posts in the topic If k is a line in xy-plane, what is the slope of k? anilnandyala 3 28 Oct 2010, 07:58
Lines k and l lie in the xy-plane. Is the slope of line k lumone 3 03 Jan 2008, 07:25
Display posts from previous: Sort by

In the xy-plane is the slope of line k equal to 0?

  Question banks Downloads My Bookmarks Reviews Important topics  

Go to page    1   2    Next  [ 24 posts ] 



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

Powered by phpBB © phpBB Group and phpBB SEO

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®.