Yes, your question certainly sparked some interest. And 2 cm is the answer everyone got.

Bob

]]>But how would I?

You could have asked me.

@Niharika, I know. I am bengali too.

]]>@bob i found the ans. as radius= 2cm. thnx for your help.

@agnishom yes its meaning is nebula

@bobbym thnx]]>

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You wrote:

Check this page out.

Arhh yes. I thought it had shades of Heron's formula in it. My book has the proof for Heron, so that sews it up nicely. Thanks.

Bob

]]>(iv) radius = y.

Why?

Bob Bundy wrote:

Note. OFB = 90 as AB is a tangent, ODB = 90 as BC is a tangent and ABC = 90 was given.

So OFBD is a square. => once we know 'y', we also know the radius.

B

]]>(iv) radius = y.

Why?

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