1)8у-3(2у-3)=7у-2(5у+8)
8y-6y+9=7y-10y-162y+9=-3y-16
2y+3y=-16-9
5y=-25
y=-25:5
y=-5
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2)5(2у-9)+6у=4(3у-2)- 21
10y-45+6y=12y-8-21
16y-45=12y-29
16y-12y=-29+45
4y=16
y=16:4
y=4
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3) 5у+7(3-у)=(5-2у)-6
5y+21-7y=5-2y-6
-2y+21=-1-2y
-2y+2y=-1-21
0-22
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4)
7у-4 (3у+5) =2-3(4у-9)
7y-12y-20=2-12y+27
-5y-20=29-12y
-5y+12y=29+20
7y=49
y=49:7
y=7