ʱ : һ 2020中考数学矩形菱形与正方形专题复?含解? - 百度文库ϿʼĶ
˾εʣκͼʣԳ·⣬ɶϵߵƽƣεжӦãе깫ʽ״ĵطеڣ1ԵD.C.Bλõȷ˵ڣ3ڵDPڵDۣڣ4KLعĵ֤
6. 2019??6֣ͼABCDУE.FֱΪAD.CDϵĵ㣬DEDF֤12
εʵóADCDSAS֤ADFաCDEɵóۣ ֤ıABCDΣ ADCD ڡADF͡CDEУADFաCDESAS 12
εʡȫεжʣεʣ֤ȫǽĹؼ
7. 2019??10֣飺ͼھABCDУE.FֱڱAD.BCϣABCDֱEF۵ʹDǡBغϣCڵC䴦PΪֱEFһ㣨E.FغϣPֱֱBE.BFĴߣֱΪMNPMPNΪڱ߹ƽıPMQN 1ͼ1֤BEBF
2֪ͼ2DE5CF2P߶EF˶ʱƽıPMQNܳ
3̽DEaCFb
ͼ3P߶EFӳ˶ʱúA.bʽӱʾQMQN֮ϵ֤
ͼ4P߶FEӳ˶ʱֱúA.bʽӱʾQMQN֮ϵҪд֤̣
33
1֤BEFBFEɽ⣨Ҳȫεʽ⼴ɣ 2ͼ2УBPEHBCHıABHEǾΣ֤PM+PNEHùɶABɽ⣮
3ͼ3УBPEHBCHSEBPSBFPSEBFɵ?BF?EHBEBFƳPMPNEH
BE?PM?BF?PN
ɴ˼ɽ⣮
ͼ4P߶FEӳ˶ʱ֤ͬQMQNPNPM𡿣1֤ͼ1У
ıABCDǾΣ ADBC DEFEFB
ɷۿ֪DEFBEF BEFEFB BEBF
2⣺ͼ2УBPEHBCHıABHEǾΣEHAB
DEEBBF5CF2 ADBC7AE2
RtABEУߡA90㣬BE5AE2 AB
34
SBEFSPBE+SPBFPMBEPNBF
?BF?EH
?BE?PM+
?BF?PN
BEBF PM+PNEH
ıPMQNƽıΣ
ıPMQNܳ2PM+PN2
3֤ͼ3УBPEHBCH
EDEBBFaCFb ADBCa+b AEADDEb EHAB
SEBPSBFPSEBF
BE?PM?BF?PN?BF?EH
BEBF PMPNEH
ıPMQNƽıΣ QNQMPMPN
ͼ4P߶FEӳ˶ʱ֤ͬQMQNPNPM
ıۺ⣬˾εʺж۱任εʣƽıεʣֱε֪ʶĹؼѧӳøߣıν⣬ѧ֤߶֮Ĺϵпѹ⣮
8.2019?㽭?6֣֪ͼABCDУEFֱڱBCCDϣBE=DFAEAF.֤AE=AF.
𰸡 ֤ıABCDΣ
35
AB=ADB=D BE=DF ABEաADF AE=CF
㡿ε
ʵAB=ADB=DȫжSASɵáABEաADFȫʼɵ֤.
92019?㽭?6֣ͼھABCDУEFڶԽBDһʹýۡAECF֤
SAS֤ABEաCDFɵAECF 𡿽⣺ӵBEDF𰸲Ψһ ֤ıABCDǾΣ ABCDABCD ABDBDC ֡BEDFӣ ABEաCDFSAS AECF
εʡȫεжʵ֪ʶĹؼȫεжпͣ
10.2019?㽭?10֣ͼEFGHĶEGֱABCDıADBCϣF
HABCDĶԽBDϣ
1֤BGDE
2EΪADе㣬FH2ABCDܳ
1ݾεʵõEHFGEHFGõGFHEHFáBFGDHEεʵõADBCõGBFEDHȫεʼɵõۣ
2EGεʵõADBCADBCAEBGAEBGõıABGEƽıΣõABEGǵõۣ 𡿽⣺1ıEFGHǾΣ EHFGEHFG GFHEHF
ߡBFG180㩁GFHDHE180㩁EHF
36