1、 2015 通州区初二（上）期末数学 10 2 20 1 2 A 0 B C D 3.141 2 2 5 A 2.5 B C D 3 2 x A x=2 B x= 3 C x= 2 D x=3 4 2 A B C D 5 2 A B C D 6 2 6 7 A 3 B C 1 D 7 2 A B C D 8 2 AD AE AF ABC ABC A AD B AE C AF D 9 2 A O OA 3 OA 1 AB Rt OAB O OB A 3.5 B C 2 D 10 2 ABC ABC=60 BC=6 CD ABC E F CD BC BE+EF A 6 B 3 C 3 D 3 6
2、11 14 3 15 16 3 20 11 3 12 3 13 3 AB BC CD DA 1+ 2+ 3+ 4= 14 3 2cm 2cm 5cm 15 4 ABC ACB=90 BAC=30 AB=2 D AB D A B CD D CD CA E ADE AD 16 4 ABC C=90 B BC AB BC E F E F EF G BG AC D BD ABC AC=8 BC=6 CD= 11 17 24 5 25 26 5 27 8 60 17 5 2 0 +| 2|+4 18 5 19 5 20 5 21 5 x 2 +3x 2=0 22 5 4 6 6 6 1 23 5 C A
3、E BC DE AC=DE BC=CE AB=CD 24 5 A B 108 27 1 0.54 1 25 6 Rt ABC ACB=90 A C l 1 Rt ABC l 2 BAC=30 BC= AB 26 6 AB 1 AB l AB D 2 1 C l C D CB A AE BC E E BC ABC E BC BAE= BCD 27 8 Rt ABC BC=AC ACB=90 D AB CD C CD l l C CD CE CF AE BF 1 D AB D A B 1 BF AD BF AD 2 D AB 2 1 参考答案与试题解析 10 2 20 1 A 0 A B B C
4、C D 3.1414 D C 2 5 D 3 x=2 A 4 A =2 B =m 2 C = D D 5 A B 6 C 3 D C 6 6 7 3 7 B 7 A “ ” “ ” A B “ ” “ ” B C “ ” “ ” C D “ ” “ ” D D 8 A 9 OB= = O OB D 10 B CD B B B F BC F CD E B F BE+EF ABC=60 CD AB BCD=30 BD= CD BD= BB BB= BC CDB B F B CDB B B F B F =C D = BC=3 C 6 11 14 3 15 16 3 20 11 = =2 2 12 3
5、 b a 2 3 b a 213 1+ 2+ 3+ 4=360 360 14 2cm 2cm 5cm 15 E AC AE=AD EDA= BAC=30 DE CD BDC=60 ACB=90 BAC=30 BC= AB=1 B=60 AC= BCD=60 BCD DCA=30 = BAC CD=BC=1 AD=CD=1 E CA AE=AD E= ADE=15 DE CD CDA=90 15 =75 ACD=180 30 75 =75 = CDA AD=AC= AD 1 1 16 GF EG BFG BEG BFG BEG SSS GBF= GBE BD ABC AC=8 BC=6 C=90
6、 AB= =10 D DH AB H BD ABC CD=DH S BAC = A C B C= BC CD+ AB DH= 6 8=24 B C C D+ A B D H =24 6CD+10DH=48 CD=3 3 11 17 24 5 25 26 5 27 8 60 17 =4 1+2 +2 =5+ 18 =2 2 +3 2 3 =2 2 +3+1=6 2 19 = = = 20 x+1 x 1 x+1 2 +6= x+1 x 1 x 2 +2x+1+6=x 2 1 2x= 8 x= 4 x= 4 x+1 x 1 x= 4 21 = = = = = x 2 +3x 2=0 x 2 +3x
7、=2 = 22 P = P = 23 BC DE ACB= E ABC DCE ABC DCE SAS AB=CD 24 1 x x+0.54 = x=0.18 x=0.18 1 0.18 25 1 Rt ABC Rt ABC l 2 Rt ABC Rt ABC l AC BB AB=AB BC= BB BAC=30 B=60 ABB AB=BB BC= BB BC= AB 26 1 l 1 2 45 ABC 90 AC ACB 90 E BC CD AB CA=CB CAB= CBA 2 CBA+ ACB=180 2 CBA 90 CBA 45 CBA 45 CBA 90 2 AB l CD AB AE BE AEB= BDC=90 BAE+ B= BCD+ B=90 BAE= BCD 27 1 1 CD EF DCF=90 ACB=90 ACB= DCF ACD= BCF BC=AC CD=CF ACD BCF AD=BF BAC= FBC ABF= ABC+ FBC= ABC+ BAC=90 BF AD 2 2 CD EF DCF=90 ACB=90 DCF+ BCD= ACB+ BCD ACD= BCF BC=AC CD=CF ACD BCF AD=BF BAC= FBC ABF= ABC+ FBC= ABC+ BAC=90 BF AD
