Joke Collection Website - Mood Talk - As shown in the figure, △ABC is an equilateral triangle, D and F are points on CB and BA respectively, and CD=BF and AD is one side to form an equilateral triangle ADE.

As shown in the figure, △ABC is an equilateral triangle, D and F are points on CB and BA respectively, and CD=BF and AD is one side to form an equilateral triangle ADE.

(2) Quadrilateral CDEF is a parallelogram.

Connect BE, ∵AB=AC, ∠EAD-∠DAB=∠BAC-∠DAB,

∴∠EAB=∠CAD, AE=AD (△ADE is equilateral Triangle),

∴△AEB≌△ADC,

∴∠ABE=∠ACD=60°. CD=EB

∵CD=BF,

∴BE=BF,

∴△BEF is an equilateral triangle.

∴EF=CD.

∵△ADC≌△CBF.

∴AD=CF.

∵AD=DE,

∴CF=DE.

∴ Quadrilateral CDEF is a parallelogram.