Answer:
Explanation:
Given: ABC is equilateral triangle.
AD = DB & BE = EC & CF = FA ------------(IV)
Proof:
D & F are midpoint of the sides AB and AC
DF =
{Midpoint theorem}
DF = BE ----------------(I)
D & E are midpoint of the sides AB and BC
DE =
{Midpoint theorem}
DE = FA ----------------(II)
E & F are midpoint of the sides BC and AC
{Midpoint theorem}
EF = AD ---------------(III)
From (I) ; (II) ; (III) ; (IV) ,
DF = DE = EF
DEF is an equilateral triangle.