Q10 of 56 Page 78

In Fig. 8.7, P is the mid-point of side BC of a parallelogram ABCD such that ∠BAP = ∠DAP. Prove that AD = 2CD.

Since ABCD is a parallelogram, AD||BC and AB is a transversal.

(Sum of co-interior angles is 180)



In ΔABP,






(opposite sides of equal angles are equal)


Now, multiply both sides by 2, we get,



(P is mid-point of BC)


(AB||CD and AD||BC)


Hence, Proved.


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