. 7-
1
- . . (1. , . , . 2. - , , . , , .)
- . . (1. , . , . 2. : a) , , b) . , , , . .)
- , 5 .( . 5. , :
.
. :
: 30, 150.)
2
- . . (1. , , . 2. 180º.)
- . . (1. - , , , , .2. . ( , ))
- MN DK B. MDB NKB. ( . MDB NKB: 1) =BN . 2) D= . 3) /_D=/_NBK . . . D NKB .
3
- . . (1. , , . : .)
- . , , . (1. , .2. - .
. , .
( )
, .
, ) - ADC AD, AD = 7 , DC = 8 . ( = (.- ). .- = + + = 7 + 8 + 8 = 23()
4
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|
- . ( ).
(:
1. (Δ ABC = Δ A1B1C1),
b
:
. , .
. , .
. , .)
- . . ( - , . - )
- , , 126. ( , = 126/2 =63 1 2 )
5
- . . (1 - , . 2 .)
- . , . (1 , ( ), ( .2 , , . , , .
, , : a) ( ) , . b) ( ) , . 1, , . . c) . 1 .d) ( ) , . 3, . 2 . ( ) . , . 4, , . , .
, , , . .).
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- , N R , MN = 11 , RN = 20 . MR. (11+20=31- MR=31)
6
- . ( ).( , , , . : , .)
- . . ( - , , . : . 1 . - 2 . . 3 (1 2 - ). .
- , , 50. . ( = (180-50) /2=65
= 180-65 = 1150)
7
- . , . ( .)
(:
1. , .
2. , .
3. , 180.
1. a b MN (c). 3 6 . , 3 6 . MN PMN, 6, , PMN 6 b MN. , ||b. , ( a ), b. . , 3 6.
)
2 . .
(1. , , .
2. : 1. , .2. .3. .)
3 , . ( 60*. . - 60*, 90*, 30* ( ))
8
- . .
(1. , , .2. : 180.
- , . ( ) , , .
- , , 42 ( . =42* .
==42* , =180-42=138* , ==138* . ==42* . ==428 , =180-42=138* , ==138* )
9
- . . (1., , .2. :
, , .
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|
.
, .)
- . .(1. , .2. , :
1) .
2) , .)
- , , 126.(180-126=54. : 126;54;126;54 - .)
10
- . , 30. ( :
90º
180º, 90º, 90º.
, 30º, .)
- . . (1. , , .2.
ABC B, :
1. , B AC, B, AC P Q.
2. P Q, E.
3. BE, AC H. BH , B AC.)
- , 55 . (++55=180 2=125=62,5 1=62,5 2=117,5 (62,5+55))
11
- .(.
:
1) ,
2) .
.
:
1) ,
2) .
1.
.
2.
. - , . ( , )
- SR S, SM SN . SMO SNO. ( SM SN , , SO . - .)
12
- . . ( , . , .
.
: , .
: , .
: . , .
- . , , , . (1. . 2. 1. . 2. , .3. . 4. , , ( )5. . .)
- AM ABK, BM , BK ABC , AC = 17 , ABC 84. ( - =/2=17/2=8,5-
- ABK =/2=84/2=42 -- ABK = 42 AM=8.5cm
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4 . 7
( )
1
, .
( ABC - AC, EN EM - , : AB BC. ANE CME ( ); , .. AE = E (E - ), BAE = BCE - , AN = MC - EN EM , . ANE CME , , EN = EM.)
2
, OAM = OAK MBS = KBS. , AK = AM, BM = BK.
(
= =, .
- , , .
: = , = .)
3
A. , 1 = 2, , 5 = 6.
( 1= 3( )
2= 4( )
.. 3=4, 1=2)
4
AB CM O. OK MOB. MOK, AOM 86.(.. AOM=86, BOM 180-86=94 .. OK - , BOK= MOK=94/2=47 : 47)
5
. , 1 = 2, , 3 = 4.
6
MP , MK OKM = 96. ( 1= 3( ) 2= 4( ) .. 3=4, 1=2
7
MOK O = 76, M 3 K. .( -
3 -
180-3 -
=180
:
+(180-3)+76=180
+180-3+76=180
-2=-76
=38 -
180-(76+38)=66 -
8
AB CM ., AM = BC.
(. . )
9
, AB = CM.
( = ,