Since X and Y are the mid points AC and AB respectively.
∴ XY∥BC
Clearly, triangles BYC and BXC are on the same base BC and between the same parallel XY and BC
∴ ar(△BYC)=ar(△BXC)
⇒ ar(△BYC)−ar(△BOC)=ar(△BXC)−ar(△BOC)
⇒ar(△BOY)=ar(△COX)
⇒ ar(△BOY)+ar(△XOY)=ar(△COX)+ar(△XOY)
⇒ ar(△BXY)+ar(△CXY)...(i)
⇒ ar(△BYX)+ar(△AXY)=ar(△AXY)+ar(△AYX)
⇒ ar(△BAX)=ar(△CAY)...(ii)
In △BAP, XY=12AP
In △CAQ, XY=12AQ
∴ AP=AQ
Clearly, triangles XAP and YAQ are between the same parallels and their bases AP and AQ are equal.
∴ ar(△XAP)=ar(△YAQ).....(iii)
Adding (ii) and (iii), we obtain
ar(△XAP)+ar(△BAX)=ar(△YAQ)ar(△CAY)
⇒ ar(△ABP)=ar(△ACQ)
Hence Proved