1、 2017-2018 120 150 8 3 24 1. 2 3 7 A 13 B 17 C 13 17 D 15 3 AB=AD ABC ADC A CB=CDB BAC= DAC C BCA= DCA D B= D=90 4. 2 4 6 8 10 12 cm A 2 4 8 B 4 8 10 C 6 8 10 D 8 10 12 5. ABC BC AB AC BC P APC 2 ABC AB BC P P B AB BC P P A. B. C D. 6. A B 3 C D 7. ABC ACB=90 ABC=60 BD ABC P BD AD=8 CP A 3 B 3.5 C 4
2、 D 4.5 8. 18 16 10 ( ) A 50 B.50 40 C.50 40 30 D.50 30 20 10 3 30 9. _ _ . 10. Rt ABC ACB=90 D AB A=30 BCD= . 11 AC=BC 1= 2 _ AOC BOC. 12 16 4 _ _ 13. ABC 90 ACB ABC ABC 1 2 3 , S S S 12 81, 225 SS S3=_ _ 14. _ _ 15. Rt ABC C 90 A B C AA AA B =20 B _ _ 16. ABCD CD CDE AEB=_ _ 17. ABC 12 BO CO OD BC
3、D OD=3 18. ABC 3 BDC BDC 120 D 60 AB M AC N MN AMN ( 10 96 ) 19.(8 ) 1 1 1 D A B C D 2 2 10 3 3 FGH 20. 8 B F C E AC DF G AB BE B DE BE E AC=DF BF=CE 1 ABC DEF 2 A=65 AGF 21. 8 Rt ABC C 90 AC 4 BC 3 AD ABC . 1 AB P DP AB 2 CD A B C D 22. 8 CD B BC=5m A 10m A D DA A BD xm 1 x AD _ _m 2 23 10 ABC D BC
4、 AB=AD=CD 1 ABC=2 C 2 B AD CA E AD BAC AE=AB 24. 10 ABC BAC=90 0 AD BC D CE ACB AB=20 AC=15 1 AD 2 AEF E F E D C B A 25. 10 ABC AB=10cm BC=6cm P C CA A A 2cm t 1 t PBC 2 P PH AB H H AB t 26. 10 A B A B A C B AC+BC A A A B C C A MON MON OM ON B C . 1 B C. 2 MON=30 OA=10, B A C 27. 12 ABC AC 6 BC 8 AB
5、 10 BCA AB D DE AC DF BC E F 1 AE BF 2 AE 3 DG 28 (12 ) ABC DEF 1 AC DF BC DE F A ABC DEF_ _ 2 AC DF BC DE 30 150 ABC DEF S1 S2 S1 S2 S1 S2 3 ABC DEF AC DF BC DE, C 30 E D DE A C B EDF S1 S2 . (2017.11) 1 2 3 4 5 6 7 8 D B C C C B C C 19. 1 1 2 2 2 3 3 3 3 FGH = ABHC AFG BGH FCH =5 6 =9 9 20. 1 4 BF
6、=CE BF+CF=CE+CF BC=EF AB BE DE BE B= 2 4 ABC DEF ACB= DFE AGF= ACB+ DFE AGF=50 9. 3 10. 60 11. A= B ACO= BCO 12. 5 5 6 13. 144 14. 50281 15. 65 16. 30 17. 18 18. 6 ABC DEF BC=EF AC=DF ABC DEF HL 21. 1 (2 ) A AC AB P. 2 6 DP AB P AD BAC CAD BAD DC AC DP AB C APD. AD AD ACD APD. AP AC SAS AP AC 4 CD P
7、D Rt ABC 90 AC 4 BC 3 AB 5. DP x DP x BD 3 x Rt DPB DPB 90 DP 2 PB 2 DB 2 x 2 1 2 3 x 2 x 4 3. 22. 1 15-x 3 2 90 AD 2 AC 2 DC 2 15-x 2 x+5 2 10 2 x=2.5 CD=5+2.5=7.5 7.5 23. 1 5 AB AD ABC ADB AD CD DAC C ADB DAC C 2 C ABC 2 C 24. 4 1 2 5 AD BAC DAB CAD BE AD DAB ABE E CAD ABE E AE AB = 22 20 15 =25 2
8、2 AB AC BC AD 20 15 12 25 AD 2 6 25. 10 (1) PBC C=90 CB=CP=6 t=6 2=3 (2) 8 7 26. 1 B C. 4 BAC=90 AEC+ ACE=90 AD BC ADC=90 DCF+ DFC=90 CE ACB DCF= ACE DFC= AFE AEF= AFE AE=AF (2) MON=30 =60 10 6 27. 1 4 AD BD DCE DCB DE CA DF CB DE DF AED DFB 90 DG AB DA DB RT DEA RT DFB DE DF,DA DB DEA DFB AE BF 2 4
9、 AE BF x RT CDE RT CDF CD CD DE DF CDE CDF CE CF 6 x 8x x 1 AE 1 3 4 DEA DFB ADE BDF EDF ADB AC 2 BC 2 AB 2 ACB 90 CED CFD ECF 90 EDF 90 ADB 90 AG GB DG 1/2AB 5 28. 1 4 2 2 2 5 S1 S2 2 3 BM AC M EN DF N BMC END 90 C EDN 30 BC ED. BMC END. BM EN. AC DF S1 S2. 3 3 . 30 150 180 S1 S2 . 30 150 S1 S2 . 30 150 S1 S2.
