《4.3.2北师大版七年级数学下册-第4章-三角形-《探索三角形全等的条件-角边角、角角边》》由会员分享，可在线阅读，更多相关《4.3.2北师大版七年级数学下册-第4章-三角形-《探索三角形全等的条件-角边角、角角边》（23页珍藏版）》请在金锄头文库上搜索。
1、3 , ,2 ,1ASAAAS 2ASAAAS,? ,? ,ABCA B C A B =AB A =A B =B ().A B C ABC,A,B,C,E,D, 1AB=AB; 2ABDAB =AEBA =BADBEC,(ASA,1 ABCDCBACB DBC ABCDCB,ABCDCB( BCCB ACBDBC,ABCDCB,ABCDCBASA,2 DABEACAB=AC, B=C,AD=AE,ACDABE,AD=AE,ACDABE,A=A AC=AB C=B ,ACDABEASA,AD=AE,6045453cm,11,.AAS,3ABCDEFADB EBC=EF.ABCDEF,BE BCE
2、F CF,ABCA+B+C180,ABCDEFASA,C180AB, F180DE, ADB E,CF,ABCDEF,4 ABCBAC90ABACmABDmCEmDE.(1)BDAAEC,(1)BDmCEmADBCEA90 ABDBAD90. ABAC BADCAE90 ABDCAE. BDAAEC,ADB=CEA=90 ABDCAE, ABAC,BDAAEC(AAS,2)DEBDCE,BDAEADCE DEDAAEBDCE,BDAAEC,1. ABCDEFABDEBEABCDEF AACDF BBCEF CAD DCF 2. ABCABCA44B67C69 A44ACAC A B C D,A,B,3. ACB=DBCABC=CDB,BC,A,B,C,D,E,F,4.ACB=DFEBC=EF ABCDEF ,B=E,A=D, AC=DF,ASA,AAS,SAS,AB=DE,ABDE,5. ABBCADDC1=2, AB=AD, ABBCADDC,B=D=90,ABCADC,ABCADCAAS,AB=AD,? ,?,𣺴1,ABC ABC ADA D ABC ABC.AD AD 仰,ABC ABC AB=ABABD=ABD. ADBCADBCADB=ADB. ABDABD ADB=ADB ABD=ABD AB=AB ABDABD.AD=AD, , ASA,
