In the adjoining figure,D and E are respectively the midpoints of sides AB and AC of △ ABC.If PQ||BC and CDP and BEQ are straight lines then prove that ar(△ ABQ)=ar(△ ACP).
In △PAC,
PA || DE and E is the midpoint of AC
So, D is the midpoint of PC by converse of midpoint theorem.
Also, DE=1/2PA-------(1)
Similarly, DE=1/2AQ-------(2)
From (1) and (2) we have
PA = AQ
∆ABQ and ∆ACP are on same base PQ and between same parallels PQ and BC
ar(∆ABQ) = ar(∆ACP)