7х + 1 - 6х - 3 = 5
х = 5 - 1 + 3
х = 7
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8х + 11 - 13 = 9х - 5
8х - 9х = -11 + 13 - 5
-х = - 3
х = 3
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3х - 5 - 7 + 4х = 2
7х = 2 + 5 + 7
7х = 14
х = 2
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8х + 5 = 119 + 7 - 3х
8х + 3х = 119 + 7 - 5
11х = 121
х = 11
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6х + 3х - 2 = 14
9х = 14 + 2
9х = 16
х = 1целая 7/9
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8у - 7у + 142 = 51
у = -142 + 51
у = - 91
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11х + 103 = 1 + 12х - 31
11х - 12х = - 103 + 1 - 31
- х = -133
х = 133