It is currently 25 Jun 2017, 17:45

### 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

# The two lines y=x and x=-4 intersect on the coordinate plane

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

### Hide Tags

Manager
Joined: 06 Jul 2011
Posts: 213
Location: Accra, Ghana
The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

23 Apr 2012, 05:54
1
KUDOS
2
This post was
BOOKMARKED
00:00

Difficulty:

5% (low)

Question Stats:

89% (01:51) correct 11% (00:39) wrong based on 118 sessions

### HideShow timer Statistics

The two lines y=x and x=-4 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x axis?

A.\sqrt{}46/3
B. 4\sqrt{}2
C. 8
D. 8\sqrt{}2
E. 16
[Reveal] Spoiler: OA
Math Expert
Joined: 02 Sep 2009
Posts: 39673
Re: The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

23 Apr 2012, 06:07
1
KUDOS
Expert's post
dzodzo85 wrote:
The two lines y=x and x=-4 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x axis?

A.\sqrt{}46/3
B. 4\sqrt{}2
C. 8
D. 8\sqrt{}2
E. 16

Look at the diagram below:
Attachment:

Area.png [ 9.69 KiB | Viewed 3101 times ]
Both legs of the right triangle equal to 4, so the area is 1/2*4*4=8.

_________________
Manager
Joined: 06 Jul 2011
Posts: 213
Location: Accra, Ghana
Re: The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

23 Apr 2012, 06:23
Thanks a lot for the explanations. I really appreciate it.
Manager
Joined: 28 Jul 2011
Posts: 238
Re: The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

27 Apr 2012, 06:39
Bunuel wrote:
dzodzo85 wrote:
The two lines y=x and x=-4 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x axis?

A.\sqrt{}46/3
B. 4\sqrt{}2
C. 8
D. 8\sqrt{}2
E. 16

Look at the diagram below:
Attachment:
Area.png
Both legs of the right triangle equal to 4, so the area is 1/2*4*4=8.

for line y=x the slope would be m = 1 and y-intersect b = 0

however,i didnot understand how did u draw the line y=x and how did u find the point of intersect. Can u explain that please?

Regards,
Manager
Joined: 28 Jul 2011
Posts: 238
Re: The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

27 Apr 2012, 06:51
kuttingchai wrote:
Bunuel wrote:
dzodzo85 wrote:
The two lines y=x and x=-4 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x axis?

A.\sqrt{}46/3
B. 4\sqrt{}2
C. 8
D. 8\sqrt{}2
E. 16

Look at the diagram below:
Attachment:
Area.png
Both legs of the right triangle equal to 4, so the area is 1/2*4*4=8.

for line y=x the slope would be m = 1 and y-intersect b = 0

however,i didnot understand how did u draw the line y=x and how did u find the point of intersect. Can u explain that please?

Regards,

i think i got it

line 1 x = -4

line 2 y=x

therefore they intersect at y = x i.e. y=-4 therefore (-4,-4)

Hope thats correct way
Math Expert
Joined: 02 Sep 2009
Posts: 39673
Re: The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

27 Apr 2012, 09:02
2
KUDOS
Expert's post
kuttingchai wrote:
Bunuel wrote:
dzodzo85 wrote:
The two lines y=x and x=-4 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x axis?

A.\sqrt{}46/3
B. 4\sqrt{}2
C. 8
D. 8\sqrt{}2
E. 16

Look at the diagram below:
Attachment:
Area.png
Both legs of the right triangle equal to 4, so the area is 1/2*4*4=8.

for line y=x the slope would be m = 1 and y-intersect b = 0

however,i didnot understand how did u draw the line y=x and how did u find the point of intersect. Can u explain that please?

Regards,

1. How to draw line y=x?

This line passes thorough all the points with equal x and y-coordinates. Now, pick two such points, for example (0, 0) and (1, 1), and draw a line through them.

This is one of the common lines for the GMAT so it's better to be familiar with it.

2. How to find intersection point of y=x and x=-4

Now, since x=-4 passes through all the points with x-coordinate equal to -4, then naturally intersection point of this line and any other line will have x-coordinate equal to -4. Next, if x-coordinate of intersection point is -4, then line y=x to pass through it, the point must have y-coordinate equal to -4 too: -4=-4. Therefore the coordinates are (-4, -4).

Hope it's clear.
_________________
Senior Manager
Joined: 01 Nov 2010
Posts: 288
Location: India
Concentration: Technology, Marketing
GMAT Date: 08-27-2012
GPA: 3.8
WE: Marketing (Manufacturing)
Re: The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

29 Apr 2012, 03:46
The two lines y=x and x=-4 intersect on the coordinate plane. What is the value of the area of the figure formed by the intersecting lines and the x axis?
Ans:
excellent explanation by Bunuel.
these type of questions are easily solved using Graph or drawing lines on co-ordinate axis.

even if you dont know how to draw a graph.
here is solution.
given
y=x and x =-4 intersect.
so, point of intersection between y=x and x =-4 will be (-4,-4)
we have to find the area covered by lines y=x,x=-4 & y=0 (i.e x-axis)
so,
and point of intersection between x=-4 and y=0 will be (-4,0)

so we have a triangle with following axis.(0,0), (-4,0) & (-4,-4)

here, if you can draw a picture of how this line will look in co-ordinate axis, you will find a right angle triangle whose altitude is 4 and base is 4.
so, area will be =1/2 x 4 x 4 = 8 (ans)

if you don't have any idea about how to draw a line or place some points on co-ordinate axis.
remember some old school day formula,
you can calculate the area of triangle by following formula:
1. first calculate the distance between three points by formula ;
Distance (a,b,c) = Sqrt[(x1-x2)^2+(y1-y2)^2]
here, a=4,b=4,c=4sqrt(2)
2. then
calculate s= (a+b+c)/2
and area of triangle is = Sqrt [(s-a)^2+(s-b)^2+(s-c)^2]
after calculation area of triangle will come as 8.

I hope my explanation will be clear.
_________________

kudos me if you like my post.

Attitude determine everything.
all the best and God bless you.

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 15980
Re: The two lines y=x and x=-4 intersect on the coordinate plane [#permalink]

### Show Tags

14 Jul 2015, 01:01
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: The two lines y=x and x=-4 intersect on the coordinate plane   [#permalink] 14 Jul 2015, 01:01
Similar topics Replies Last post
Similar
Topics:
1 On a two-dimensional coordinate plane, the line y = x^2 - x^3 touches 4 10 Jun 2016, 15:39
1 In the coordinate plane OP=1, ∠Q=90, and ∠POQ=30, y/x=? 2 03 Feb 2016, 22:42
4 The two lines y = x and x = -4 intersect on the coordinate plane. If z 5 13 Jun 2017, 18:30
4 Line A is drawn on a rectangular coordinate plane. If the coordinate p 5 15 Jun 2017, 20:28
8 On a two dimensional coordinate plane, the curve y=x^2 - x^3 6 31 Oct 2016, 14:27
Display posts from previous: Sort by

# The two lines y=x and x=-4 intersect on the coordinate plane

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

 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®.