conjetura abc

∠B+∠C=180°-∠A

∠A=∠A1=40°

Entonces ∠B+∠C=140

∠BEF+∠CFE=360-∠B-∠C=220

∠BEA1+∠CFA1=∠BEF+∠CFE-∠A1EF-∠A1FE

∠A1EF+∠A1FE =180-∠A1=140

Entonces ∠BEA1+∠CFA1=220-140=80°Mapa de Baidu