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信息发布者:
解:全等,如图所示
解 在​$\triangle ADB$​和​$\triangle BCA$​中,
​$\{\begin {array}{l}\ \mathrm {A}D = BC,\\BD = AC,\\AB = BA,\end {array}.$​
​$∴\triangle ADB\cong \triangle BCA(\mathrm {SSS})$​.
​$∴∠ABD = ∠CAB$​,​$∠DAB = ∠CBA$​,​$∠D = ∠C$​.
​$∴∠DAB - ∠CAB = ∠CBA - ∠ABD$​,
即​$∠DAE = ∠CBE$​.
在​$\triangle DAE$​和​$\triangle CBE$​中,
​$\{\begin {array}{l} ∠D = ∠C,\\AD = BC,\\∠DAE = ∠CBE,\end {array}.$​
​$∴\triangle DAE\cong \triangle CBE(\mathrm {ASA})$​.
​$∴DE = CE$​.
三边
边边边
SSS
A'B'
B'C'
C'A'
SSS
AE=DF
D
2.
(1) AE=DF
(2) D