第一问全等的话EC=CDAC=BC∠ACE=∠BCD∴全等第二问：因为全等所以∠EAC=∠B=45°，∠CAB=45°，所以∠EAD=90°所以AD²+AE²=DE²···················································楼上的先生，你都做了半个小时了
