=sin (20+40)=sin60= корень из 3/2
8-6=2 8-4=4 8-2=6 8-8=0 6-4=2 6-2=4 6-6=0 4-2=2 4-4=0 2-2=0
Х+21 3/19-3 18\19=21 17\19
х= -21 3/19+ 3 18\19 +21 17\19
х= 3 (-3\19+18\19 +17/19)
х= 3(15\19+17\19)
х=4 13\19
8/14=x/35
14x=8*35
14x=280
x=280:14
x=20
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7/28=x/12
28x=7*12
28x=84
x=84:28
x=3
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4/x=6/18
6x=4*18
6x=72
x=72:6
x=12
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14/10=21/x
14x=10*21
14x=210
x=210:14
x=15
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x/10=18/60
60x=10*18
60x=180
x=180:60
x=3
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45/25=18/x
45x=25*18
45x=450
x=450:45
x=10
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