30-28

magical cook · Posted: Sat Aug 25, 2007 1:28 pm Post subject: 30-28

Hi,

Can anyone help with this problem?

Thanks.

beny · Posted: Sat Aug 25, 2007 3:02 pm Post subject:

I don't know that much about circles, but I think the answer is E. If the center of the circle is at (0,100000), then the radius would be pretty large...

magical cook · Posted: Sun Aug 26, 2007 5:14 pm Post subject:

Sorry, I am still confused.... Embarassed

but the answer seems to be E.

Can you explain a bit more to get to the answer?

beny · Posted: Sun Aug 26, 2007 6:44 pm Post subject:

As long as the center of the circle is equidistant from the two points (in this case, on the y-axis), the radius potential is unlimited. A larger and larger radius would only create a circle in which the two points form a smaller and smaller chord.

magical cook · Posted: Sun Aug 26, 2007 7:02 pm Post subject:

Okay I think I understand now Smile

- thanks very much!

lalitgmat · Posted: Mon Aug 27, 2007 7:58 am Post subject:

|------(0,0)-------|
A | (B)
|<---- Say 'x'
|
(c)

From (0,0) to (b) is 4. From (0,0) to (c), center of circle is x.
Hence by Pythagoras Theorem Smile

r^2 = x^2 + 4^2

For maximum value of (r), x^2 + 14 should be maximum. And there is NO limit for a maximum number or even a perfect square no.

Ans is (E).
=========== Now Question is What is the Min value of Radius =====
For you only..