Question

in a cyclic quadrilateral, if (angle B-angleD) =60 degree, show that the smaller of the two angle is 60 degree

Answer 1

angleB-angleD=60 degree (given)............(1)
angleB+angleD=180.............(2)
( because these are the angles of a cyclic quadrilateral)
so, from 1 &2 . we conclude that....
2 angleD=180-60
2angleD=120
angleD=120/2
=60degree