abhas Active member


 | Subject: Maths icse Sample Question.[circle] Mon Jan 28, 2008 10:54 am | |
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orca
 | Subject: Re: Maths icse Sample Question.[circle] Thu Jul 03, 2008 2:36 pm | |
| Connect point A and O, extend AO to meet BC at D and the circle at E.
As triangle ABC is an isosceles triangle, AD is perpendicular bisector of BC.
So AD = sqrt(10^2 - 6^2) = 8
In Rt triangle ABE, BD is an altitude. So AB^2 = AD*AE AE = (AB^2)/AD = 100/8 = 25/2
As AE = 2R So R = AE/2 = 25/4 |
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