GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 16 Oct 2019, 22:32

### 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

# Does line y = mx + c intersect X axis?

Author Message
TAGS:

### Hide Tags

Manager
Joined: 10 Nov 2010
Posts: 168
Location: India
Concentration: Strategy, Operations
GMAT 1: 520 Q42 V19
GMAT 2: 540 Q44 V21
WE: Information Technology (Computer Software)
Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

03 Feb 2011, 13:16
1
5
00:00

Difficulty:

35% (medium)

Question Stats:

57% (01:04) correct 43% (01:09) wrong based on 186 sessions

### HideShow timer Statistics

Does line y = mx + c intersect X axis?

(1) m < 0
(2) c > 0

_________________
The proof of understanding is the ability to explain it.
Director
Status: -=Given to Fly=-
Joined: 04 Jan 2011
Posts: 788
Location: India
Schools: Haas '18, Kelley '18
GMAT 1: 650 Q44 V37
GMAT 2: 710 Q48 V40
GMAT 3: 750 Q51 V40
GPA: 3.5
WE: Education (Education)
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

03 Feb 2011, 20:43
2
2
Statement 1 Alone:
It is given that the slope of the line is negative. Thus, at one point or other, it will intersect the x-axis.

The point at which it will intersect the x-axis is:

mx + c = 0 or x = -c/m

SUFFICIENT

Statement 2 Alone:
It is given that the y intercept is greater than 0. This means that the line intersects the y axis at a point y>0.
It is not necessary for the line to intersect the x-axis because the line can be parallel to the x-axis while having a positive y intercept

Ans: 'A'
_________________
Intern
Joined: 10 Sep 2013
Posts: 22
Location: India
Concentration: Accounting, Finance
GMAT Date: 10-25-2013
GPA: 3.66
Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

26 Sep 2013, 23:58
1
1
Does line y = mx + c intersect X axis?

(1) m < 0
(2) c > 0
_________________
Strive for Excellence....!!!!!
Current Student
Status: Chasing my MBB Dream!
Joined: 29 Aug 2012
Posts: 1100
Location: United States (DC)
WE: General Management (Aerospace and Defense)
Re: Does the line Y=MX+C intersect X axis?  [#permalink]

### Show Tags

27 Sep 2013, 00:12
1
KK23 wrote:
Does line Y=MX+C intersect X axis?

A)M<0

B)C>0

Statement 1 : M<0 means slope is negative,
so at some point the line will intersect x.

intersection point :
mx+c=0, so x= -c/m... (A is sufficient)

Statement 2: y intercept is greater than 0, so it will intersect y>0.

This line may be parallel to x-axis with positive y intercept.. so not sufficient.

Answer is A Hope it is correct. i guess i came across this problem earlier in Club forum
_________________
Intern
Joined: 10 Sep 2013
Posts: 22
Location: India
Concentration: Accounting, Finance
GMAT Date: 10-25-2013
GPA: 3.66
Re: Does the line Y=MX+C intersect X axis?  [#permalink]

### Show Tags

27 Sep 2013, 00:41
GNPTHBALAJI wrote:
KK23 wrote:
Does line Y=MX+C intersect X axis?

A)M<0

B)C>0

Statement 1 : M<0 means slope is negative,
so at some point the line will intersect x.

intersection point :
mx+c=0, so x= -c/m... (A is sufficient)

Statement 2: y intercept is greater than 0, so it will intersect y>0.

This line may be parallel to x-axis with positive y intercept.. so not sufficient.

Answer is A Hope it is correct. i guess i came across this problem earlier in Club forum

+1 Kudos....

Thanks a lot !!!

Any idea is if we have a quadratic equation f(x)=Ax^2+C=y will this intersect with x axis if we know that A<0 or C>0??
_________________
Strive for Excellence....!!!!!
Math Expert
Joined: 02 Sep 2009
Posts: 58390
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

27 Sep 2013, 02:01
1
KK23 wrote:
Does line y = mx + c intersect X axis?

(1) m < 0
(2) c > 0

Check here for theory: math-coordinate-geometry-87652.html

Hope it helps.
_________________
Intern
Joined: 27 Sep 2013
Posts: 1
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

27 Sep 2013, 02:30
2
The first statement (m<0) alone is sufficient to answer but not the second statement (c>0) alone.

The reason is that if m=0, then the line is parallel to Y-axis, hence won't intersect the X-axis. Since m<0, it is a line with decreasing slope, hence the line will intersect and cut the X-axis at a certain stage.

As for the statement 2 (c>0), it may or may not intersect the X-axis as the line may be parallel to X - axis and still have a positive c. Example : y = 5 is a straight line with c = 5 >0 and won't ever cut the X-axis.
Intern
Joined: 01 Sep 2016
Posts: 20
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

19 Sep 2016, 05:01
mx + c = 0 or x = -c/m
.pls explain this part.pls
Math Expert
Joined: 02 Sep 2009
Posts: 58390
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

19 Sep 2016, 05:16
sanaexam wrote:
mx + c = 0 or x = -c/m
.pls explain this part.pls

mx + c = 0;

mx = -c;

x = -c/m.
_________________
Intern
Joined: 01 Sep 2016
Posts: 20
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

19 Sep 2016, 05:26
y=mx+c.how did y become 0?
Math Expert
Joined: 02 Sep 2009
Posts: 58390
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

19 Sep 2016, 05:33
sanaexam wrote:
y=mx+c.how did y become 0?

x-intercept is the value of x for y = 0.

Check here for theory: math-coordinate-geometry-87652.html
_________________
Intern
Joined: 01 Sep 2016
Posts: 20
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

19 Sep 2016, 05:42
ok.now understood:)
Non-Human User
Joined: 09 Sep 2013
Posts: 13204
Re: Does line y = mx + c intersect X axis?  [#permalink]

### Show Tags

02 Feb 2019, 07:05
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: Does line y = mx + c intersect X axis?   [#permalink] 02 Feb 2019, 07:05
Display posts from previous: Sort by