In a right-angle ΔABC, ∠ABC = 90°, AB = 5 cm and BC = 12 cm. The radius of the circumcircle of the triangle ABC is

Answer: Option C

According to question,
ABC is a right angled triangle

∴ By using Pythagoras theorem
AC² = AB² + BC²
AC² = (5)² + (12)²
AC² = 25 + 144
AC² = 169
AC = $$\sqrt{169}$$
AC = 13 cm
BD = I_R = Circumradius = $$\frac{AC}{2}$$
∴ I_R = $$\frac{13}{2}$$
I_R = 6.5 cm