如图，D在BC边上，△ABC≌△ADE，∠EAC=40°，则∠ADE的度数为___．求详细过程

更新时间2018-08-02 21:05:37

如图，D在BC边上，△ABC≌△ADE，∠EAC=40°，则∠ADE的度数为___．

△ABC ≌ △ADE

∠BAC = ∠DAE

∴∠BAD = ∠EAC = 40°

△ABC ≌ △ADE

∠ABC = ∠ADE

AB = AD

∠ABD = (180° - ∠BAD)/2 = 70°

∴ ∠ADE  = 70°