If AB = 5 cm, AC = 12 cm and AB ⊥ AC, then the radius

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If AB = 5 cm, AC = 12 cm and AB ⊥ AC, then the radius of the circumcircle of ∆ ABC is

1. 6.5 cm
2. 6 cm
3. 5 cm
4. 7 cm

Correct Option: A

According to question , we draw a figure of triangle ABC circumscribes a circle with centre O

Here , AB = 5 cm, AC = 12 cm and AB ⊥ AC
BC = Diameter
From ∆ABC ,
∴ BC = √AB² + AC²
BC = √5² + 12² = √25 + 144
BC = √169 = 13 cm

∴ OB = circum-radius =	BC	=	13	= 6.5 cm
	2		2