D, E, F are the mid points of side AB, BC, AC prove that BDEF is a parallelogram whose area is half that of `Delta` ABC

Explanation

`"DE parallel to AB" =>"DE parallel to BF"`

`"similarly FE parallel to BD"->"BDEF is a parallelogram"`

`"similarly DCEF and AFDE is a parallelogram "`

`" In parallelogram BDFE, DF is a diagonal"`

`ar (/_\BDF)=ar(/_\DEF)->"eq(1)"`

`"In parallelogram DCEF, DE is a diagonal"`

`ar(/_\DCE)=ar(/_\DEF)->"eq(2)"`

`therefore "similarly ar"(/_\AFE)=ar(/_\DEF)->"eq(3)"`

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