在三角形abc中,AB=AE,E是BC上一点,D是AC上一点,且AE=AD,若∠DEC=20°,求∠BEA得度数

∵∠DEC=180-∠AEB-∠AED,∴∠AEB+∠AED=160∵AB=AE,AE=AD∴∠AEB=∠ABE,∠AED=∠ADE∴∠ABE+∠ADE=160,∴∠BAD=360-(∠ABE+∠ADE)-(∠AEB+∠AED)=40,∵∠AEC=∠ABE+∠BAE=∠AED+∠DEC∴∠ABE+∠BAE+∠EAD=∠AED+∠D...