题目

如图2，∠BOE＝2∠AOE，OF平分∠AOB，∠EOF＝20°．求∠AOB．    答案：)解：∵∠BOE＝2∠AOE，∠AOB=∠BOE+∠AOE， ∴∠BOE=∠AOB，····················································································· 5分 ∵OF平分∠AOB， ∴∠BOF=∠AOB，························································如图，在□ABCD中，E、F分别在边BA、DC的延长线上，已知AE＝CF，P、Q分别是DE和FB的中点，求证：四边形EQFP是平行四边形．