<span>sin (-11pi/6)=<span>sin (-12pi/6+pi/6)=<span>sin (-2pi+pi/6)=sin(pi/6)=1/2</span></span></span>
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1)3х= -7
х= -7:3
х= -7/3
х= -2 1/3
2)-100х= -13
х=13:100
х=0,13
3)7х-х= -16+4
6х= -12
х= -12: 6
х= -2
4) -5х+2х=8-13
-3х= -5
х= -5:(-3)
х=5/3
х=1 2/3
5)4у-6у=17-15
-2у=2
у=2:(-2)
у= -1
6)8х=9+7
8х=16
х=16:8
х=2
7)2у=11+5
2у=16
у=16:4
у=4
8) х=5+2
х=7
9)8х-9х= -5-11+13
-х= -3
х=3