24.△ABC是等邊三角形,點(diǎn)D在BC上,點(diǎn)E,F(xiàn)分別在射線AB,AC上,且DA=DE=DF.
(1)如圖1,當(dāng)點(diǎn)D是BC的中點(diǎn)時(shí),則∠EDF=
°;
(2)如圖2,點(diǎn)D在BC上運(yùn)動(dòng)(不與點(diǎn)B,C重合).
①判斷∠EDF的大小是否發(fā)生改變,并說明理由;
②點(diǎn)D關(guān)于射線AC的對(duì)稱點(diǎn)為點(diǎn)G,連接BG,CG,CE.
依題意補(bǔ)全圖形,判斷四邊形BECG的形狀,并證明你的結(jié)論.