1/3х=1/2
1/2:1/3 =1,5
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7+2х=0
2х=-7 х=-7 ÷ (-2) х=7÷2 х=2,5
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5-4х=х-15
-4х-х=-15-5 -5х=-20 5х=20 х=4
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х+2(3х-2)=10
х+6х-4=10 7х=14 х=2