Question

Prove that in △ABC external bisector of angle A, external bisector of angle B and

internal bisector of angle C are concurrent.​

Answer 1

Answer:

Correct option is

D

90  

∘

 

In ∠ABC , BD is the internal bisector

Then ∠ABD=∠DBC ,  

In ∠ABF ,BE is the external bisector  

Then ∠ABD=∠DBC ,  

The line FBC is strata line  

Then ∠ABD∠DBC+∠ABF+∠EBF=180

=2(∠ABD+∠ABF)=180

=(∠ABD+∠ABF)=90  

0

 

Then angle between the internal and external bisectors is 90  

0

 

Step-by-step explanation: