A circle is inscribed in a triangle ABC right-angled at B. If AB=5 cm and BC=12 cm, then what is the radius of the circle?

Explanation

For a right-angled triangle, the hypotenuse is AC = \sqrt{5^2+12^2} = 13 cm. The inradius r can be found using the formula r = \frac{a+b-c}{2}. Thus, r = \frac{5+12-13}{2} = 2 cm.

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