内容正文:
17 2021. 4.29
1 2 3 4 5 6 7 8 9 10
A B B B C C B C D C 1 3 5
3 30
11. 10 12.
2
74 −x 13. -2 a 2 14. 100° 15. 4 x 7
16. 45° 17. 20 18. 20° 19. 5 15 20. 16
21. 1
⎪⎩
⎪
⎨
⎧
=
=
5
2
1
y
x
2
2
1
x 3
22. 1 2 3 2
23. 3 x 1 x 2 x = -2 3x 4 = -2a a = 1
24. 1 ADC BEC = 180° BEC AEB = 180°
ADC = AEB ABC BAD = EBC C
BAD = EBC ABC = C
2 ABC C AFE BFD
25. 1
⎩
⎨
⎧
=+
=+
45023
95065
yx
yx
⎩
⎨
⎧
=
=
75
150
y
x
A B 100 75
2 130 100 a 100 75 50 a 1460
a 42
a a 43 A 43
26. 1 C = 90° ABC A = 90°
ADE = ABC ADE A = ABC A = 90°
DE AB
2 G GH DC GHD = 90°
AG EAC GEA GHA
DGA = AGH
D DGA AGH = D 2 DGA = 90°
3 K = 22.5°
27. 1 AC = 4 BC = 10
2 d = t
25
4-
5
16
3 P
7
20
7
24
B
$