SOLUTION: Find the area of a triangle with perimeter of 210 cm and which contains an inscribed circle with circumference of 20π cm

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Question 1112174: Find the area of a triangle with perimeter of 210 cm and which contains an inscribed circle with circumference of 20π cm
Answer by ikleyn(52754) About Me  (Show Source):
You can put this solution on YOUR website!
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The circumference of the circle = 20pi cm  ====>  the radius of the circle is  r = 10 cm.


The area of a triangle with the perimeter P and the inscribed circle radius r is equal to


Area A = %281%2F2%29%2AP%2Ar.


    See the lesson
        Proof of the formula for the area of a triangle via the radius of the inscribed circle 
    in this site.


In your case the area A = %281%2F2%29%2A210%2A10 = 1050 sq. cm.