In a right-angled triangle ABC, ∠ABC = 90°, AB = 5

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

1. 7.5 cm
2. 6 cm
3. 6.5 cm
4. 7 cm

Correct Option: C

As per the given in question , we draw a figure right-angled triangle ABC ,

Given that , ∠ABC = 90°, AB = 5 cm and BC = 12 cm.
AC = Diameter of circum circle = √AB² + BC²
AC = √5² + 12² = 13 cm
∴ Circum-radius = 13 ÷ 2 = 6.5 cm