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If in a triangle ABC, r(1)+r(2)+r(3)=9r,...

If in a triangle `ABC, r_(1)+r_(2)+r_(3)=9r`, then the triangle is necessarily

A

right angled

B

equilateral

C

obtuse angled

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
B
We know that in a `Delta ABC`
`r_(1)+r_(2)+r_(3)=4R+r`
`rArr 4R+r=9r`
`rArr R = 2r`
Thus, `Delta ABC` is equilateral.
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