Q6 of 65 Page 128

In Fig. 6.21, A, B and C are points on OP, OQ andOR respectively such that AB || PQ and AC || PR.Show that BC || QR.

Given that in triangle POQ, AB parallel to PQ

Hence,


(Basic proportionality theorem)


Now,


Therefore,


Using Basic proportionality theorem, we get:



From above equations, we get



BC is parallel to QR (By the converse of Basic proportionality theorem)


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