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

 It is currently 20 Oct 2019, 04:26 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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.  If Line k in the xy-plane has equation y = mx + b, where m

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:

Hide Tags

Manager  Joined: 06 Apr 2010
Posts: 103
If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

2
19 00:00

Difficulty:   55% (hard)

Question Stats: 62% (01:46) correct 38% (02:07) wrong based on 448 sessions

HideShow timer Statistics

If Line k in the 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).
Math Expert V
Joined: 02 Sep 2009
Posts: 58434
If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

4
9
Manager  Joined: 18 Sep 2009
Posts: 243
If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

3
7
If Line k in the 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)

I have a doubt in stmnt (2). K intersects the line with equation y=2(x)+3 at point (2,7) means for the line y=2(x)+3 slope is 2,but with this we cannot able to find slope of the line K. is my reasoning is right. please explain
General Discussion
Math Expert V
Joined: 02 Sep 2009
Posts: 58434
If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

4
1
2
If Line k in the xy-plane has equation y = mx + b, where m and b are constants, what is the slope of k?

$$y=mx+b$$ is called point-intercept form of equation of a line. Where: $$m$$ is the slope of the line; $$b$$ is the y-intercept of the line; $$x$$ is the independent variable of the function $$y$$.

So we are asked to find the value of $$m$$.

(1) k is parallel to the line with equation y = (1-m)x + b +1 --> parallel lines have the same slope --> slope of this line is $$1-m$$, so $$1-m=m$$ --> $$m=\frac{1}{2}$$. Sufficient.

(2) k intersects the line with equation y = 2x + 3 at the point (2, 7) --> so line k contains the point (2,7) --> $$7=2m+b$$ --> can not solve for $$m$$. Not sufficient.

_________________
Manager  B
Joined: 22 Feb 2012
Posts: 84
Schools: HBS '16
GMAT 1: 740 Q49 V42 GMAT 2: 670 Q42 V40 GPA: 3.47
WE: Corporate Finance (Aerospace and Defense)
Re: coordinate geometry  [#permalink]

Show Tags

1
Quote:
If Line k in the 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)

I have a doubt in stmnt (2). K intersects the line with equation y=2(x)+3 at point (2,7) means for the line y=2(x)+3 slope is 2,but with this we cannot able to find slope of the line K. is my reasoning is right. please explain

My 2 cents:

Questions is asking you what is the value of M

so

1) Since k and this line with slope (1-m) are parallel

then m = 1 - m or m = 1/2

thus it is sufficient

2) we know that the point 2, 7 is on the line line y = mx + b

so 7 = 2m + b

But we know nothing else so we cannot solve for m thus it is insufficient
Intern  Status: ISB 14...:)
Joined: 26 May 2012
Posts: 28
Location: India
Concentration: Strategy
Schools: ISB '14 (A)
GMAT 1: 750 Q51 V39 GPA: 3.62
WE: Engineering (Energy and Utilities)
Re: Coordinate Geometry 2  [#permalink]

Show Tags

For line K, y=mx+b implies slope=m

From Statement-1,

As slopes of parallel lines are equal, m = (1-m)

m=1/2
Statement-1 is sufficient.

From statement-2,

line K passes through (2,7)
7=2.m + b
m = (7-b)/2
Not sufficient.

Ans:A
Manager  S
Joined: 21 Jul 2018
Posts: 186
If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

Hi chetan2u, VeritasKarishma, Bunuel, amanvermagmat, gmatbusters,

I did not understood the bold part in below question, can any please assist.

Bunuel wrote:
If Line k in the xy-plane has equation y = mx + b, where m and b are constants, what is the slope of k?

$$y=mx+b$$ is called point-intercept form of equation of a line. Where: $$m$$ is the slope of the line; $$b$$ is the y-intercept of the line; $$x$$ is the independent variable of the function $$y$$.

So we are asked to find the value of $$m$$.

(1) k is parallel to the line with equation y = (1-m)x + b +1 --> parallel lines have the same slope --> slope of this line is $$1-m$$, so $$1-m=m$$ --> $$m=\frac{1}{2}$$. Sufficient.

(2) k intersects the line with equation y = 2x + 3 at the point (2, 7) --> so line k contains the point (2,7) --> $$7=2m+b$$ --> can not solve for $$m$$. Not sufficient.

_________________
______________________________
Press +1 Kudos if my post helped you a little and help me to ulcock the tests Wish you all success

I'd appreciate learning about the grammatical errors in my posts

Please let me know if I'm wrong somewhere and help me to learn Retired Moderator V
Joined: 27 Oct 2017
Posts: 1259
Location: India
Concentration: International Business, General Management
GPA: 3.64
WE: Business Development (Energy and Utilities)
Re: If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

1
Hi

I couldd not get your query, the principle is as below:  Attachment: 1.jpg [ 20.17 KiB | Viewed 2510 times ]

Attachment: 2.PNG [ 18.18 KiB | Viewed 2516 times ]

Gmatprep550 wrote:
Hi chetan2u, VeritasKarishma, Bunuel, amanvermagmat, gmatbusters,

I did not understood the bold part in below question, can any please assist.

Bunuel wrote:
If Line k in the xy-plane has equation y = mx + b, where m and b are constants, what is the slope of k?

$$y=mx+b$$ is called point-intercept form of equation of a line. Where: $$m$$ is the slope of the line; $$b$$ is the y-intercept of the line; $$x$$ is the independent variable of the function $$y$$.

So we are asked to find the value of $$m$$.

(1) k is parallel to the line with equation y = (1-m)x + b +1 --> parallel lines have the same slope --> slope of this line is $$1-m$$, so $$1-m=m$$ --> $$m=\frac{1}{2}$$. Sufficient.

(2) k intersects the line with equation y = 2x + 3 at the point (2, 7) --> so line k contains the point (2,7) --> $$7=2m+b$$ --> can not solve for $$m$$. Not sufficient.

_________________
Manager  S
Joined: 21 Jul 2018
Posts: 186
Re: If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

gmatbusters wrote:
Hi

I couldd not get your query, the principle is as below:  Attachment:
1.jpg

Attachment:
2.PNG

Gmatprep550 wrote:
Hi chetan2u, VeritasKarishma, Bunuel, amanvermagmat, gmatbusters,

I did not understood the bold part in below question, can any please assist.

Bunuel wrote:
If Line k in the xy-plane has equation y = mx + b, where m and b are constants, what is the slope of k?

$$y=mx+b$$ is called point-intercept form of equation of a line. Where: $$m$$ is the slope of the line; $$b$$ is the y-intercept of the line; $$x$$ is the independent variable of the function $$y$$.

So we are asked to find the value of $$m$$.

(1) k is parallel to the line with equation y = (1-m)x + b +1 --> parallel lines have the same slope --> slope of this line is $$1-m$$, so $$1-m=m$$ --> $$m=\frac{1}{2}$$. Sufficient.

(2) k intersects the line with equation y = 2x + 3 at the point (2, 7) --> so line k contains the point (2,7) --> $$7=2m+b$$ --> can not solve for $$m$$. Not sufficient.

Hi gmatbusters

Apologies for not highlighting proper issue,

I was not able to get following part.

slope of this line is 1−m1−m, so 1−m=m1−m=m

Even if slope is m then also how 1-m = m? I feel that "m" mentioned in equation is different.
_________________
______________________________
Press +1 Kudos if my post helped you a little and help me to ulcock the tests Wish you all success

I'd appreciate learning about the grammatical errors in my posts

Please let me know if I'm wrong somewhere and help me to learn Intern  Joined: 12 Jun 2019
Posts: 2
Re: If Line k in the xy-plane has equation y = mx + b, where m  [#permalink]

Show Tags

Parallel lines have same slopes buddy

Posted from my mobile device Re: If Line k in the xy-plane has equation y = mx + b, where m   [#permalink] 29 Jul 2019, 22:11
Display posts from previous: Sort by

If Line k in the xy-plane has equation y = mx + b, where m

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne  