1、 2015 平谷区初二（上）期末数学 30 3 . 1 3 A 1 B 2 C 3 D 4 2 3 A B C D 3 3 x A B C D 4 3 AB CD BC ABE C=34 BED A 17 B 34 C 56 D 68 5 3 0 A 1 B 2 C 3 D 4 6 3 A B C D 7 3 A B C D 8 3 A B P PA=16m PB=12m AB A 15m B 17m C 20m D 28m 9 3 n A 12 B 11 C 8 D 3 10 3 ABC AC BH D E DE F BF AC H B BK AC D E K K B AC BH A B C
2、 D 32 4 11 4 = 12 4 0 a 13 4 a b a+b= 14 4 ABC C=90 AC= D BC ADC=2 B AD=2 BC= 15 4 x y =0 y x 16 4 3 5 17 4 ABC C=90 AC=BC AD BAC BC D DE AB E BDE 6 AB= AC= 18 4 58 19-27 5 28 6 29 7 19 5 ABC AB=AC D E BC BD=CE AD=AE 20 5 21 5 22 5 23 5 24 5 25 5 150 10 26 5 x 1 x 2 =1 1 x 2=1 x 1=1 x=2 x= 2 x= 2 27
3、 5 ABC AB=AC 1 AC D BD BD E AE=AB AE EAC AF AF DE F 2 1 CF E= ACF 28 6 a 0 a=6 |a|=|6|=6 |a| a=0 |a|=0 |a| a 0 a= 6 |a|=| 6|=6= 6 |a| |a| |a|= 1 2 |a| |a| 3 1 x 2 29 7 1 ABC EDF ACB= F=90 A= E=30 D AB AD=BD=CD EDF D DE DF AC M K 1 2 3 CDF=0 60 AM+CK MK “ ” “ ” “ =” 2 4 CDF=30 AM+CK MK “ ” “ ” 3 1 0
4、CDF 60 AM+CK MK 参考答案与试题解析 30 3 . 1 1 3 4 3 C 2 1 = D 3 x+3 0 x 3 C 4 AB CD ABC= C=34 BC ABE CBE= ABC=34 BED= C+ CBE=68 D 5 B 6 B 7 A B =2|a| C =2 D A 8 16 12 AB 16+12 4 AB 28 D 9 1 n n=11 B 10 ABC AC BH K K B AC B BK AC D E D E DE F BF AC H BH D 32 4 11 = 2 2 12 a 2=0 a+3 0 a=2 2 13 4 5 a=4 b=5 a+b=
5、9 9 14 ADC=2 B ADC= B+ BAD B= DAB BD=AD=2 Rt ADC C=90 DC= = =1 BC=BD+DC=2+1=3 3 15 x 2=0 y+ =0 x=2 y= y x =2 2 16 3 3 3 5 =3+3+5=11 3 3 5 5 =3+5+5=13 11 13 11 13 17 C=90 AD BAC BC D DE AB CD=DE AC=BC B=45 BDE BE=x CD=DE=x BD= x BDE 6 x+x+ x=6 x=6 3 AC=BC=x+ x=6 3 + 6 3 =3 AB= AC= 3 =6 6 3 18 C O= C
6、O DO =D O CD =C D DOC D O C ODC O D C SSS O= O 58 19-27 5 28 6 29 7 19 A AF BC F AB=AC BF=CF BD=CE DF=EF AD=AE 20 = + +3 = 3 +2 +3 =2 21 = = = =2 22 =3 2 +2 +3=8 3 23 x x 1 x 2 +2 x 1 =x x 1 24 = + = =x 1 x=1+ =1+ 1= 25 x x=15 x=15 15 26 x “ ” “ ” x 1 x 2 =x 1 x+2=x x x= 1 2 2x= 3 2 x= x= x= 27 1 2
7、AB=AC AE=AB AE=AC AF EAC EAF= CAF AEF ACF AEF ACF SAS E= ACF 28 1 a 0 a=3 a=0 a 0 a= 3 2 =|a| 3 1 x 2 x 1 0 x 2 0 =x 1+ 2 x =1 29 1 Rt ABC D AB AD=BD=CD= AB B= BDC=60 A=30 ACD=60 30 =30 CDE=60 CDF=60 CKD=90 CDA AM K =CM K AM K =KM C CK=0 AM=0 AM+CK=MK 2 1 ACD=30 CDB=60 A=30 CDF=30 EDF=60 ADM=30 AM=MD CK=KD AM+CK=MD+KD MKD AM+CK MK 3 AM+CK MK A ED G GK GM GD G A DE AD=GD GM=AM GDM= ADM Rt ABC D AB AD=CD=GD A= E=30 CDA=120 EDF=60 GDM+ GDK=60 ADM+ CDK=60 GDK= CDK GDK CDK GDK CDK SAS GK=CK GM+GK MK AM+CK MK
