SOLUTION: A triangle has side lengths 20, 21 and 29. Find the radii of the inscribed and circumscribed circles

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Question 350077: A triangle has side lengths 20, 21 and 29. Find the radii of the inscribed and circumscribed circles
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Hi,
Note: Area of a triangle = sqrt%28s%28s-a%29%28s-b%29%28s-c%29%29 where a,b,c are the lengths of the sides and s is the semiperimeter:
s = 1/2(20+21+29) = 35
.
A+=+sqrt%28s%28s-a%29%28s-b%29%28s-c%29%29
A+=+sqrt%2835%2A15%2A14%2A6%29
A+=+210
.
Note: Area of a triangle =%28abc%2F4R%29 , where a, b and c are lengths of the sides of the triangle and R is the radius of the circle circumscribing the triangle
R=+abc%2F4A
.
R=+20%2A21%2A29%2F%284%2A210%29
.
R+=+14.5 the radius of the circumscrbed circle
.
Note: radius of the incsribed cirle = A/s, where s is the semiperimeter
r+=+210%2F35+=+6 radius of the inscribed circle