黑龙江省哈尔滨市南岗区虹桥初级中学2020-2021学年 下学期七年级期中数学(五四制)学科试卷

1 2021 2 3 4 5 6 2021 1 2 3 4 5 6 7 8 9 10 C D D C A C A B C C 11. 6 5x 12. m 1 13. 7 14. 3 2 15. 6 16. 2 17. 5 18. 26 19. 130° 50° 20. 8 21. 1 ⎩ ⎨ ⎧ −= = 1 3 y x 2 ⎩ ⎨ ⎧ = = 7 5 y x 22. 1 x 2 1 2 x 3 23. 1 2 3 4 24. 1 BED = 70° 2 GDB ADF GAD 25. 1 A100 B75 2 21 26. 1 2 3 CBH = β AGB = 3β Rt CBH CHB = 90° CBH = 90° β DGH D = 180° DGH DHG = 180° 90° β 90° β = 2β  D = ABC  ABC = 2β  ABH = ABC CBH = β EAG = GAH = α  EAH = ACB ABC 2α = 90° 2β α = β 3β = 4β  β = 15° α = 60° 3β = 45°  ABH = 15°  ABH 2 HAM = 45°  HAM = 45°  AHM MAH = 90°  AMH = 90° AM GB DE AB S AGB= EGABAMGB ⋅⋅=⋅⋅ 2 1 2 1 1.5AB 2 = AB
EG EG = 3 G AB 3 27. 1 A 1 0 B 0 -2 chengzhi7970 2 OAB = α BAP = " # 180° α OBA = β ABP = " # 180° β 7
P = 180° " # 180° α " # 180° β = " # α β = 45° 
P 45° 3 GAC = a GCA = b CBG = c 50° a 30° b = 180° 30° b c 180° 2b = 180° 50° a 180° 2b c = 180° ⎪⎩ ⎪ ⎨ ⎧ °= °= °= 10 40 60 γ β α  NGA = 90°
AGB = 40°  MNC =
GAC NGA = α 40°  MNC = 60° 40° = 20° MNC 20°