- 问题详情:在△ABC中,∠C=90°,∠B=∠22.5°,DE垂直平分AB交BC于E,BC=2+2,则AC=( )A.1 B.2 C.3 D.4【回答】B.【解析】∵DE垂直平分AB,∴∠B=∠DAE,BE=AE,∵∠B=22.5°,∠C=90°,∴∠AEC=∠CAE=45°,∴AC=CE,∴2AC2=AE2,∴AE=AC,∴BC=BE+CE=AE+AC=AC...
- 12760
- 问题详情:如图,在△ABC中,DE∥BC,若,DE=2,则BC的长为 。【回答】6知识点:相似三角形题型:填空题...
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- 问题详情:已知,如图,在△ABC和△EDB中,∠ACB=∠EBD=90°,点E在BC上,DE⊥AB交AB于F,且AB=ED.求*:DB=BC.试题*练习册*在线课程分析:由题意得∠D+∠DEB=90°,∠ABC+∠DEB=90°,则∠ABC=∠D,则△ABC≌△EBD,从而得出DB=BC.解答:*:∵∠EBD=90°,DE⊥AB∴∠D+∠DEB=90°,∠ABC+∠DEB=90°,(1分)∴∠ABC...
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- 问题详情:已知:如图1,点A是线段DE上一点,∠BAC=90°,AB=AC,BD⊥DE,CE⊥DE,(1)求*:DE=BD+CE.(2)如果是如图2这个图形,我们能得到什么结论?并*.【回答】*:(1)∵BD⊥DE,CE⊥DE,∴∠D=∠E=90°,∴∠DBA+∠DAB=90°,∵∠BAC=90°,∴∠DAB+∠CAE=90°,∴∠DBA=∠CAE,∵AB=AC,∴△ADB≌△CEA,∴BD=AE,CE=AD,∴DE...
- 10438
- WorkareaII:includes2subgradeconstructionteams,1structureconstructionteamand1drainsconstructionteam.Newcountrysideconstructionofthecontentsofwhatisit?...
- 19093
- Andsuchaninhibitionmightnecessitatedenovoproteinsynthesis.Performingdenovosequencingwithoutknowingaminoacidmassesisverynovel.Adenylosuccinatelyase(ADSL)isabifunctionalenzymecatalyzingdenovopurinesynthesisandpurinenucleotiderecycling.and§706(2)(F)pro...
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- 问题详情:如图,已知:AB=DE且AB∥DE,BE=CF.求*:∠A=∠D.【回答】解:*:∵AB∥DE,∴∠B=∠DEF,∴BE=CF,∴BC=EF,在△ABC和△DEF中,AB=DE,∠B=∠DEF,BC=EF∴△ABC≌△DEF(SAS),∴∠A=∠D.知识点:三角形全等的判定题型:解答题...
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- DEPOSADASMONTERO,LuisM.CyranoDEBergeracmeetsCinderella.WashedCrepeDEChine:Silk.DEdaphne'ssilkyheartilyforwho?ThisisMadameDERothschild'sprivateroom.SoweusetheDEBroglieformula.Ilove,totalisridiculous,IabandonedasourDEpatinagemDE!AftersupperDEbosssayI...
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- 问题详情:Infact,mostofuswould theconsequencesofstupid decisionstakenbyothers.A.handle B.solveC.suffer D.follow【回答】C知识点:单词题型:选择题...
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- Financingdejuretoupgradethelevelofschoolfinancialmanagement;Mostofthemasdejurepopulation,whoseagestructureandsexstruc-turewereofimbalance,haddevelopedtheNortheasternfrontierregionwiththeminoritynationalitiesthere....
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- 问题详情:如图,点A在DE上,AC=CE,∠1=∠2=∠3,则AB与DE的数量关系为( )A.AB>DE B.AB=DEC.AB<DE D.无法确定【回答】B知识点:三角形全等的判定题型:选择题...
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- 问题详情:已知:如图,DE⊥AC,BF⊥AC,AD=BC,DE=BF,.求*:AB∥DC【回答】.∵DE⊥AC,BF⊥AC,∴∠AED=∠CFB=90°∠AFB=∠CED=90°…………1分在Rt△ADE和Rt△BCF中∴Rt△ADE≌Rt△BCF(HL)…………3分∴AE=CF…………4分∴AE+EF=CF+EF 即AF=CE…………5分在△AFB和△CED中…………7分...
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- 问题详情:已知:如图,AB∥DE,AC∥DF,BE=CF.求*:AB=DE.【回答】*:∵AB‖DE,AC‖DF∴∠ABC=∠DEF,∠ACB=∠DFE(同位角相等)∵BE=CF∴BC=BE+EC=CF+EC=EF∴ΔABC≌ΔDEF∴AB=DE(全等三角形对应边相等)知识点:三角形全等的判定题型:解答题...
- 22422
- [Latin]defactorecognitiondefactosegregationisasrealassegrationimposedbylaw;adefactostateofwar.Thegeneraltookdefactocontrolofthecountry.Theywillbedefactoinastateofwar.Thebusinesscapitalizationisthedefactofinancialplanningstagefortheairline.Typically,s...
- 6960
- DE值不同的麦芽糊精替代变*淀粉,对其微胶囊化有很大影响;在费林氏法测定还原糖的条件下,比较了果糖和葡萄糖的还原力;分别用葡萄糖和淀粉水解糖为原料,研究了异构化过程中DE值与果糖含量的关系。...
- 29288
- einsteindebroglieformuladebrogliewavelength...
- 31672
- 1、Thegoalofnavigatingconflictistode-escalate.2、Afterward,gobackovertheprocesswithyourteamandlearnfromyourmistakes.Andrememberthattherewillbesomepeopleyoucannotde-escalatewithoutcoercion....
- 28985
- EveningdressisderigueurattheCasino.KatimexplainedthatthiskindofbehaviourisderigueurinGambia.instructionastowhenandwhereasilkhatisderigueur....
- 10409
- 问题详情:如图1,点A是线段DE上一点,∠BAC=90°,AB=AC,BD⊥DE,CE⊥DE,(1)求*:DE=BD+CE.(2)如果是如图2这个图形,BD、CE、DE有什么数量关系?并*.【回答】*:(1)∵BD⊥DE,CE⊥DE,∴∠D=∠E=90°,∴∠DBA+∠DAB=90°,∵∠BAC=90°,∴∠DAB+∠CAE=90°,∴∠DBA=∠CAE,且AB=AC,∠D=∠E=90°,∴△ADB≌△CEA(AAS),∴BD=AE,CE=AD,...
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- 问题详情:如图,AB=DE,AC=DF,BE=CF.求*:AB∥DE.【回答】【考点】全等三角形的判定与*质;平行线的判定.【分析】求出BC=EF,根据SSS*△ABC≌△DEF,推出∠B=∠DEF,根据平行线判定推出即可.【解答】*:∵BE=CF,∴BE+EC=CF+EC,∴BC=EF,在△ABC和△DEF中,,∴△ABC≌△DEF(SSS),∴∠B=∠DEF,∴AB∥DE.知识...
- 9552
- 1、Noustrouvonsdetoutdansnotremémoire.Elleestuneespècedepharmacie,delaboratoiredechimie,oùonmetauhasardlamaintant??tsurunedroguecalmante,tant??tsurunpoisondangereux.-在我们的记忆里可以找到一切。记忆就是一个*房或化学实验室,人们在里头偶然取镇定剂,要么...
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- Teamspirit;espritdecorpsTheregimenthadastrongespritdecorps.Theregimenthadastrongespritdecorps.theespritdecorpsofafootBallteam.LeRougeetleNoiretlespritdelutteindividuellechezStendhal;Nuclearreactoroperatorssaythattheirprofessionistypifiedbythesamekind...
- 10633
- 问题详情:﹣22÷﹣[22﹣(1﹣×)]×12【回答】解:原式=------------------2分 =---------3分 =------4分 =--------------5分 =-3-38------------------------6分 =-41---------------------------7分知识点:有理数...
- 32431
- 问题详情:如图,在△ABC中,AB=AC,DE是过点A的直线,BD⊥DE于D,CE⊥DE于E.(1)若BC在DE的同侧(如图1)且AD=CE,请写出:BA和AC的位置关系 .(不必*)(2)若BC在DE的两侧(如图2)其他条件不变,请问(1)中AB与AC的位置关系还成立吗?若成立,写出*过程;若不成立,说明理由。【回答】(1)BA⊥AC ...
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- 问题详情:如图,在△ABC中,DE∥BC,且DE=3cm,=,则BC=______cm,=______.【回答】9知识点:相似三角形题型:未分类...
- 11712