In Fig. 15.80, ABCD is a trapezium in which AB||DC. Prove that ar(Δ AOD) = ar(Δ BOC).

Given that,

ABCD is a trapezium with AB DC


To prove: Area ( = Area (


Proof: Since,


ΔABC and ABD are on the same base AB and between the same parallels AB and DC


Therefore,


Area (Δ ABC) = Area (Δ ABD)


Area (Δ ABC) – Area (Δ AOB) = Area (ΔABD) – Area (Δ AOB)


Area (Δ AOD) = Area (Δ BOC)


Hence, proved


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