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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

62% (02:08) correct
38% (01:07) wrong based on 253 sessions

HideShow timer Statistics

What is the length of the chord AB

(1) The center of the circle is at the Origin and the chord AB is parallel to y-axis with one end of it at (8,6) (2) The equation of the circle is x^2 + y^2 = 100

Answer has to be A. It is parallel to y axis and we already know its length on top of the x-axis, i.e. 6. Now since the chord will mirror on the other side of x-axis, i.e when y is negative, we can double 6 to get the length of the chord, which will be 12 . We do not need the size of the circle and the size of the circle itself will not be sufficient. Hence the answer has to be A.
_________________

"Nowadays, people know the price of everything, and the value of nothing."Oscar Wilde

Statement A : It is given that the center of the circle is 0 (0,0) & 1 end point of the Chord AB A (8,6). Further AB is parallel to the Y - Axis. From the above we can form the triangle AOB with height of 6 & base of 8. Using Pytha theorem we can find the Hypoth OA which is the radius. From this it is possible to find the coordinates of B using Pythag theorem

Thus Sufficient

Statement B : From the eqn of circle we can only compute the radius of circle which is 10 & thus is insufficient

Hope this helps
_________________

Giving +1 kudos is a better way of saying 'Thank You'.

Statement A : It is given that the center of the circle is 0 (0,0) & 1 end point of the Chord AB A (8,6). Further AB is parallel to the Y - Axis. From the above we can form the triangle AOB with height of 6 & base of 8. Using Pytha theorem we can find the Hypoth OA which is the radius. From this it is possible to find the coordinates of B using Pythag theorem

Thus Sufficient

Statement B : From the eqn of circle we can only compute the radius of circle which is 10 & thus is insufficient

Hope this helps

Why do you need to use the pythagorean theorem. Its pretty simple as it is. 8,6 means one half is 6 units long since it is parallel to y axis. Just double (since the circle is centered at origin) \(6*2=12\) which is the length of the cord. Had it not been parallel to the y-axis, it was a whole different story altogether and pythagorean theorem could have come in.
_________________

"Nowadays, people know the price of everything, and the value of nothing."Oscar Wilde

(1) The center of the circle is at the Origin and the chord AB is parallel to y-axis with one end of it at (8,6) (2) The equation of the circle is x^2 + y^2 = 100

What is the length of the chord AB

(1) The center of the circle is at the Origin and the chord AB is parallel to y-axis with one end of it at (8,6) --> as the circle is centered at the origin and chord AB is parallel to y-axis then the other end of the chord will be mirror reflection around x-axis:

Attachment:

1.PNG [ 12.79 KiB | Viewed 2557 times ]

So, the length of AB=12. Sufficient

(2) The equation of the circle is x^2 + y^2 = 100 --> just gives us an equation of a circle centered at the origin with radius equal to 10. No info about the chord. Not sufficient.

Re: What is the length of the chord AB [#permalink]

Show Tags

28 Jul 2014, 21:59

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: What is the length of the chord AB [#permalink]

Show Tags

14 Aug 2014, 04:43

equation of circle given. one end of point given and given that chord is parallel to y axis => equation of chord given. so can find other point and hence the length of chord.

Re: What is the length of the chord AB [#permalink]

Show Tags

14 Aug 2014, 04:43

equation of circle given. one end of point given and given that chord is parallel to y axis => equation of chord given. so can find other point and hence the length of chord.

Re: What is the length of the chord AB [#permalink]

Show Tags

04 Jun 2016, 02:47

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.
_________________

Its been long time coming. I have always been passionate about poetry. It’s my way of expressing my feelings and emotions. And i feel a person can convey...

Written by Scottish historian Niall Ferguson , the book is subtitled “A Financial History of the World”. There is also a long documentary of the same name that the...

Post-MBA I became very intrigued by how senior leaders navigated their career progression. It was also at this time that I realized I learned nothing about this during my...