1、 2017 120 ; 120 10 3 30 . 1 A B C D 2. A B C D 3. 3 8 A. 5 7 B. 7 9 C. 7 D. 9 4. ABC 3 5 7 DEF 3 3x 2 2x 1 x A B. 4 C 3 D 5. . A.SSS B.SAS C.AAS D.ASA 6. B= D=90 CB=CD 1=30 2= A 30 B. 40 C. 50 D. 60 7. 4cm 6cm 8cm 10cm. A 1 B 2 C 3 D 4 A B C D A B C D 9 13 12 15 8. ABC AB=AC D BC 1 ABD ACD 2 AD BC 3
2、 B= C 4 AD ABC A 1 B. 2 C. 3 D. 4 9. ABC AC AD BD DAC 80 B A 40 B 35 C 25 D 20 10 4 n ( n ) A 2n 1 B. 3n 2 C. 4n 2 D. 4n 2 8 3 , 24 . 11. 40 _ _. 12. ABE ACD AB=10cm A=60 B=30 AD=_ cm ADC=_ 13. AB CD O A= B _ AOC BOD. 14. ABC DEF ABC 18 AB=5,EF=6, AC=_. 15. A+ B+ C+ D+ E+ F+ G 16. A 10m 15 10m 15 _
3、A _ B _ C _ E _ D _ A C B O D B E A D G C F 17 A m 17. , 2=55 1=_. 18. BD ABC DE AB E S ABC=36cm2 AB=18cm BC=12cm DE cm. 7 66 19. 8 3 180 20. 8 B E C F AB DE A D AC DF ABC DEF BE CF 16 A 15 15 E D B C A E D C A B H F21.(8 ) B C D ABC CDE BE AC F AD CE H (1) BCE ACD (2) FH/BD 2 22 8 ) C E ABD BD AB AE AD CE CD D 70 ECD 150 B 23 ( 10 ) AD ABC BE ABD 1 ABE=15 , BAD=40 BED 2 ABC 40 BD=5 E BC 24. 12 ABC AB=AC AB BD, AC CE, CE=BD. ED BC F. DF EF 25. 12 ABC ,AB=CB, ABC=90 ,F AB , E BC , AE=CF. (1) :Rt ABE Rt CBF; (2) CAE=30 , ACF .
