In a right angled triangle ABC, the lengths of the sides containing the right angle are 5 cm and 12 cm respectively. A circle is inscribed in the triangle ABC. What is the radius of the circle (in cm)?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 2
The side which contains the right angle are 12 and 5.
The hypotenuse of the triangle = 144 + 25 = 169 = 13 cm.
Inradius = (Area of triangle)/(semi - perimeter)
Area of triangle ABC = 1/2 × 12 × 5 = 30
Semi perimeter = (12 + 5 +13)/2 = 15
Inradius = 30/15 = 2 cm.