Median of a triangle divides it into two triangles of equal area.
In △ABC,AD is the median, so Ar(△ADB)=Ar(△ADC)..........(i)
In △BEC,ED is the median, so Ar(△BED)=Ar(△CED)............(ii)
(i)−(ii)
⟹Ar(△ADB)−Ar(△BED)=Ar(△ADC)−Ar(△CED)
∴Ar(△ABE)=Ar(△ACE)