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( )
( 10 4 )
1 D 2 R 3 D 4 A 5 C 6 B 7 C 8 A 9 B 10
C
( 4 5 20 )
( 2 8 16 )
15 ( 1 ) A ( a , 3 2a ) A x 2 a
3
a - 2 3 a - 3 ( 2 ) A x 2 a 3 a
o 3 A ( a 3 2 o )
0
.
i
2
b O
17 A B ï B C 1 , C A ï B B B C ,
2 ,
S
( T
- 2 , SM 2 C
A I B i C ï = SM , 1
+ S
AB C
+ S
A
+ S A B C - 2 + 2 + 2 + 1 7
18 ( 1 ) x = 0 2× + 4 - 4 v 0 O 2× + 4 r = 2 A (2 , 0 ) B (o
, 4 )
( 2 ) SL A B o = X 2 >< 4 - 4
1
2
. m . $ ,
Z D B E + L B E D = 9 0 ° Z B E D = 66 °
.
Z D B E = 24
°
/ AD J B C , Z C = 68 ° ,
( 2 ) A B C 5 2
( 2
5 )
3
2
a 3 A x
16 ( 1 ) - + b k 0 ,
k 0 , b - 0 ( 2 )
4 5 °
( 2 8 16 )
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( 3 ) t i t , A ' B ' C ' - 3 x 5
1
X 1 x 5
1
X 2 X 2
1
X 3 X 3 - 6
2 2 2
( 12 )
2 + ( 1 )
x A B ( 8 0 x )
A O O ) B 5 0 ( 8 0 x ) = ( x 30 )
14× + 20 ( 100 x ) + 10 ( 80 x ) + 8 ( x 30 ) = 8× + 2 560 3 0 x 80
( 2 ) ( 1 ) y 8 r + 2 56 0y x x 80
x = 80 , v 8 X 80+ 2 560 - 1920 ,
2 0 A
B
( 12 )
2 2 ( ) A B C A 4 A B C + C B 18o ° 4 0 ° - 14 o ° D B C