做八年级数学补充细腿就相当于考试,小编整理了关于苏科版八年级上册数学补充习题答案2017,希望对大家有帮助! 苏科版八年级上册数学补充习题答案2017(一) 探索三角形全等的条件(4) 1、∵ AB ∥ CD, ∴ ∠ABE = ∠CDF. ∵ AE ⊥ BD,CF ⊥ BD, ∴ ∠AEB = ∠CFD = 90°. 在△ABE和△CDF中, ∵ ∠ABE = ∠CDF,∠AEB = ∠CFD, AE = CF, ∴ △ABE ≌ △CDF(AAS).∴ AB = CD. 2、∵ △ABC ≌ △DCB, ∴ AB = DC,∠A = ∠D.在△AOB和△DOC中, ∵ ∠A = ∠D,∠AOB = ∠DOC,AB = DC, ∴ △AOB ≌ △DOC(AAS). 3、(1) 在△ABE和△ACD中, ∵ ∠A = ∠A,∠B = ∠C,AE = AD, ∴△ABE ≌ △ACD(AAS). (2)∵△ABE ≌ △ACD, ∴ AB = AC,AB - AD = AC - AE,即DB = EC.在△BOD和△COE中, ∵ ∠DOB = ∠EOC,∠B = ∠C, DB = EC, ∴ △BOD ≌ △COE(AAS). 苏科版八年级上册数学补充习题答案2017(二) 探索三角形全等的条件(5) 1、∵ B是EC的中点, ∴ BE = BC. ∵ ∠ABE = ∠DBC, ∴∠ABE + ∠ABD = ∠DBC + ∠ABD, 即∠DBE = ∠ABC.在△DEB和△ACB中, ∵ ∠DBE = ∠ABC,∠D = ∠A, BE = BC, ∴ △DEB ≌ △ACB( AAS). ∴DE = AC. 2、∵ CD ⊥ AB,EF ⊥ AB, ∴ ∠CDB = ∠EFA = 90°, ∵ AD = BF, ∴ AD + DF = BF + DF,即AF = BD.在△CBD和△EAF中, ∵ CD = EF, ∠CDB = ∠EFA,BD = AF, ∴△CBD ≌ △EAF(SAS). ∴∠A = ∠B. 3、∵ ∠AFB = ∠AEC,∠B = ∠C,AB = AC, ∴ △ABF ≌ △ACE(AAS). ∴ ∠BAF = ∠CAE. ∴ ∠BAF - ∠EAF = ∠CAE - ∠EAF,即∠BAE = ∠CAF. 苏科版八年级上册数学补充习题答案2017(三) 探索三角形全等的条件(6) 1、连接BD. ∵ AB = CB, AD = CD, BD = BD, ∴ △ABD ≌ △CBD(SSS). ∴ ∠A = ∠C. 2、∵AB = DC,AC = DB,BC = CB, ∴ △ABC ≌ △DCB(SSS). ∴ ∠ABC = ∠ DCB,∠ACB = ∠DBC. ∴ ∠ABC - ∠DBC = ∠DCB - ∠ACB, 即∠1 = ∠2. 3、△ABC ≌ △CDA( SSS),△ABE ≌ △CDF( SAS), △ADF ≌ △CBE(SAS).证明略. 苏科版八年级上册数学补充习题答案相关文章: 1.八年级上册数学补充习题答案 2.2016苏科版八年级下册数学补充习题答案 3.苏科版八年级上册数学教案 4.苏科版初三下册数学补充习题答案 5.北师大版2016九年级下册数学补充习题答案
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