A triangle ABC has a circle inscribed within it with sides a, b, c. The area of the triangle is A. What is the radius of the inscribed circle?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e.
r = A / s
where s = (a + b + c) / 2
s = (a + b + c) / 2
r = A / [(a + b + c) / 2]
r = A × 2 / (a + b + c)
r = 2A / (a + b + c)