∆ABC is a right angled triangle with AB = 6 cm, AC

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∆ABC is a right angled triangle with AB = 6 cm, AC = 8 cm, ∠BAC = 90°. Then the radius of the incircle is

1. 4 cm.
2. 2 cm.
3. 6 cm.
4. 3 cm.

Correct Option: B

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

Given , AB = 6 cm, AC = 8 cm , ∠BAC = 90°
From ∆ ABC,
BC = √AB² + AC²
BC = √6² + 8²
BC = √36 + 64
BC = √100 = 10 cm.

∴ Semi–perimeter of ∆ ABC = s =	6 + 8 + 10	=	24	= 12 cm.
	2		2

Area of ∆ ABC =	1	× AC × AB =	1	× 8 × 6 = 24 Sq. cm.
	2		2

∴ In-radius =	∆	=	24	= 2cm.
	s		12