?$ (1) $?證明：∵?$BD，$??$CE$?是?$\triangle ABC$?的高
∴?$∠ADB=∠AEC = 90°$?
?$ $?在?$\triangle ABD$?和?$\triangle ACE$?中
?$ \begin {cases}∠ADB=∠AEC\\AD = AE\\∠A=∠A\end {cases}$?
∴?$\triangle ABD≌\(chéng)triangle ACE(\mathrm {ASA})$?
?$ (2)$?解：?$ ∠1=∠2$?
理由：∵?$\triangle ABD≌\(chéng)triangle ACE$?
∴?$AB = AC，$??$∠ABD=∠ACE$?
又∵?$AB = AC，$?∴?$∠ABC=∠ACB$?
∴?$∠ABC-∠ABD=∠ACB-∠ACE，$?即?$∠1=∠2$?
