4,0) and (-4,0) are the co-ordinates on a circle X. What is : PS Archive
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 22 Jan 2017, 18:03

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

4,0) and (-4,0) are the co-ordinates on a circle X. What is

Author Message
CEO
Joined: 15 Aug 2003
Posts: 3460
Followers: 67

Kudos [?]: 863 [0], given: 781

4,0) and (-4,0) are the co-ordinates on a circle X. What is [#permalink]

Show Tags

18 Sep 2003, 11:50
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions

HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

(4,0) and (-4,0) are the co-ordinates on a circle
X. What is the maximum possible radius of the circle?
Intern
Joined: 28 Aug 2003
Posts: 36
Location: USA
Followers: 0

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

Show Tags

18 Sep 2003, 13:43
praetorian123 wrote:
(4,0) and (-4,0) are the co-ordinates on a circle
X. What is the maximum possible radius of the circle?

These are two points on X-axis and y-coordinates are 0. So, infinite number of circles can be drawn with the center on y-axis as (4,0) and (-4,0) are equidistant from the Y-axis. The smallest circle possible will have a radius of 4. However, I couldn't determine the maximum possible radius. I will wait for others to comment on this. Thanks!
Intern
Joined: 15 Jul 2003
Posts: 20
Followers: 0

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

Show Tags

19 Sep 2003, 02:21
If there are only two points then the maximum possible radius of a circle is ' Infinity "

u need exactly three points to define a circle.
_________________

abhay pathania
GE US

CEO
Joined: 15 Aug 2003
Posts: 3460
Followers: 67

Kudos [?]: 863 [0], given: 781

Show Tags

19 Sep 2003, 03:17
Edeal

you said there are two points on the X axis.. but these lie ON the CIRCLE.

i think i am missing something big time...can you explain this please?

How will you draw infinite circles passing through the same two points?

We know that the two points lie on the circle and we also know that their y - coordinates are 0

-4,0..........................(0,0)...............................4,0

My question :

Can you show me how the radius is greater than 4 and still the circle passes through both these points.

thanks
Senior Manager
Joined: 21 Aug 2003
Posts: 257
Location: Bangalore
Followers: 1

Kudos [?]: 11 [0], given: 0

Show Tags

19 Sep 2003, 04:59
praet.. lets look at the problem this way:
How many circles are possible that have the points A (4,0) & B (-4,0) as its chord. ( a chord is line segment whose end points lie on a circle).

Now consider line segment AB - how many circles can have AB as its chord - infinite.
Also diameter of a circle is always greater in length than the chord (draw and see for urself). So all the circles that i will draw will have diameters greater than this chord length and infinite such circles are possible. The minimum dia ( & radius) is possible when chord itself is diameter of the circle. In that case min. radius = 4.
i hope this clarifies.
-vicks
ps: one question: How many unique solutions does the following system of equations have:
x - 2y = 6
2.5x = 5y + 15
CEO
Joined: 15 Aug 2003
Posts: 3460
Followers: 67

Kudos [?]: 863 [0], given: 781

Show Tags

19 Sep 2003, 05:05
Vicky wrote:
praet.. lets look at the problem this way:
How many circles are possible that have the points A (4,0) & B (-4,0) as its chord. ( a chord is line segment whose end points lie on a circle).

Now consider line segment AB - how many circles can have AB as its chord - infinite.
Also diameter of a circle is always greater in length than the chord (draw and see for urself). So all the circles that i will draw will have diameters greater than this chord length and infinite such circles are possible. The minimum dia ( & radius) is possible when chord itself is diameter of the circle. In that case min. radius = 4.
i hope this clarifies.
-vicks
ps: one question: How many unique solutions does the following system of equations have:
x - 2y = 6
2.5x = 5y + 15

I cant understand why this simple fact slipped my mind

Your question : How many unique solutions does the following system of equations have:
x - 2y = 6
2.5x = 5y + 15 ==> x -2y= 6

Both the equations are the same...Infinite.

Is that correct!
Senior Manager
Joined: 21 Aug 2003
Posts: 257
Location: Bangalore
Followers: 1

Kudos [?]: 11 [0], given: 0

Show Tags

19 Sep 2003, 05:09
bingo..!!
we just need to recognize the traps that testmakers want us to fall in...
19 Sep 2003, 05:09
Display posts from previous: Sort by