1、 2017-2018 2017.11 1. 2. 3. . 3 24 1 2 3 4 5 6 7 8 B D C B A C D D 3 30 9. 2 10. -2 11. 512. 40 70 100 13. 18 14. 10 15. 16 16.52 17. 8 18. 48 5 19-20 7 21-24 8 25-26 10 66 19.(1) x 2 =4 x= 2 5 (2) =3 4 3= 4 10 20. AB DE B DEF 2 ABC DEF B DEF AD BC EF ABC DEF 8 21. ADB BAC 4 ADB BCA SAS 6 ABD BAC AE
2、=BE 8 22. 3 , 6 , P 8 23. 1 AO= 5 2 -3 2=4 4 2 OD= 5 2 -(4-1) 2=4 BD=OD-OB=4-3=1 8 24. BE DE 1 E AC BE=1/2AC DE= 1 2 AC 5 BE=ED 6 BF=DF 8 25 (1) AOD BOE ,2 A B BEO . 1 2, 1 , BEO AEC BED . AEC BED , AB AE BE AEC BED AEC BED ASA . 4 2 . AEC , BED EC ED C BDE EDC , 1 42 , 69 EC ED C EDC 69 BDE C . 8 26. 1 4 2 ACB DCE CA=CB CD=CE ACB= ACD= BCE ACD BCE ACD BCE SAS AD=BE ADC= BEC DCE CDE= A D E BEC=135 AEB= BEC 6 CD=CE CM DE DM=ME=5 Rt ACM AM 2 +CM 2 =AC 2 BE=AD=x AC= 6+x x+5 2 +5 2 = x+6 2 x=7 AE=AD+DM+ME=17 8
