А) 0,8х - 9 = 3х + 13 б) 1,3у - 14,2 = 11,3 - 3,8у в) 2,7х + 4,7 = 2,3х + 9,54 г) 1,3у -...

$0.8x - 9 = 3x + 13 \\ 0.8x - 3x = 13 + 9 \\ - 2.2x = 22 \\\\ x = - \frac{22}{2.2}\\ \\ x = - 10$
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$1.3y - 14.2 = 11.3 - 3.8y \\ 1.3y + 3.8y = 11.3 + 14.2 \\ 5.1y = 25.5 \\ \\ y = \frac{25.5}{5.1} \\ \\ y = 5$
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$2.7x + 4.7 = 2.3x + 9.54 \\ 2.7x - 2.3x = 9.54 - 4.7 \\ 0.4x = 4.84 \\ x = 12.1$
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$1.3y - 2.9 = 2.3 - 0.7y \\ 1.3y + 0.7y = 2.3 + 2.9 \\ 2y = 5.2 \\ y = \frac{5.2}{2} \\ y = 2.6$
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Готово.
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