广东省湛江市某实验中学2021-2022学年八年级下学期期末数学试卷

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ST஺FUBF,Vᫀ.ூFV௃FY(1)YRtzXABCNB=90°,ZA=60°,AZC=90°-^4=30°._ᙠRtACD.ZC=30°6CD=4t.DF=l.CD=2t,2.DF=AE%(2)'DF//AB,DF=AE,123AEFO567123aA£)=AEN123AEFO5:3ᓽ60-4/=2/,FY=10,ᓽa=10N123AEFQ5:3(3)1233arHIC3ᳮᵫ᝞g:BNEDF=90°NDE//BC..ZADE=ZC=30°.AD=2AE

25VCD=4r,.DF=2t=AE,.'.AD=4t,.4r+4/=60,.•"=kNZEDF=90°2lBFfDF,.123BEDFHIC3.ூmn௃o⚪q⌕ὃtuvwv3Ḅឋyஹ67123Ḅᑨ|ஹ:3ḄឋyஹIC3Ḅឋy>}m~67123ஹ:3ஹIC3Ḅᑨ|5F⚪Ḅᐵ.25.(10ᑖ)᝞u/Yy=-m+6xஹyᑖBmA,B,u/iYy=/+lyBmC,u/uḄmHE(1)᝞1,mEḄᙶ᪗H2,EmAḄᙶ᪗Y(2)ᙠ(1)ḄgD(a,0)HxḄmm஺xḄᚖᑖu/u/IBmMஹN,m8ஹCஹMஹNH⚔mḄ123H67123E஻Ḅ
(3)᝞2,u/u/2Yy=-b-3ḄmH5ᔲᙠmB,8E=3ூᑖ᪆௃(1)ᵫmEḄᙶ᪗ᔠᦪ¢mḄᙶ᪗ᱯ¤ᓽ¥¦mEḄᙶ᪗§ᑭᵨª|«ᦪ¬ᓽE¦uIḄF᪆®=0E¦xḄ
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27y=~^-x+bὶ½u/ஹ/2ḄF᪆ᡂCD¾y=-^-x-3ox=18+6bF:y=-9-2bm.Ḅᙶ᪗H(18+66,-9-26).,;BE=BF,0EஹFᙳᙠu/-1=-18-6b,FYb--AL,7MNu/ḄF᪆H.-ÝÞᦑᙠm8,MNu/ḄF᪆Hà=.ூmn௃o⚪ὃtáᦪ¢mḄᙶ᪗ᱯ¤ஹ67123ḄឋyâFᐗCD~67123Ḅឋy5F⚪Ḅᐵ.

28