SOLUTION: A circle is inscribed in a right triangle that has a hypotenuse of 182 cm. If the perimeter of the triangle is 420 cm, what is the radius of the inscribed circle?

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Question 1190317: A circle is inscribed in a right triangle that has a hypotenuse of 182 cm. If the perimeter of the triangle is 420 cm, what is the radius of the inscribed circle?
Answer by ikleyn(52797) About Me  (Show Source):
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A circle is inscribed in a right triangle that has a hypotenuse of 182 cm.
If the perimeter of the triangle is 420 cm, what is the radius of the inscribed circle?
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For any right triangle, the radius of the inscribed circle is 

    r = %28a+%2B+b+-+c%29%2F2,     (1)


where "a" and "b" are the legs lengths and "c" is the hypotenuse length.


We are given the perimeter P = a + b + c = 420 cm  and  the hypotenuse length  c= 182 cm,


therefore, we can easily compute the radius of the inscribed circle

    r = %28%28a+%2B+b+%2B+c%29+-+2c%29%2F2 = P%2F2-c = 420%2F2-182 = 210 - 182 = 28 centimeters.    ANSWER

Solved.

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Regarding formula  (1)  and its proof,  see the lesson

    - The radius of a circle inscribed into a right angled triangle

in this site.