If the bisectors of the base angles of a triangle enclose an angle of 135°, prove that the triangle is a right triangle.

Given bisector og the base angles of a triangle enclose an angle of 135o

i.e. BOC = 135o


But,


135o = 90o + A


A = 135o – 90o


A = 45o (2)


= 90o


Therefore, is right angled triangle right angled at A.


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