Ответ:

3.5x - 2.3x + 3.8 = 4.28

1.2x + 3.8 = 4.28

1.2x = 4.28 - 3.8

1.2x = 0.48

x = 0.48/1.2

x = 0.4  

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4.7y - (2.5y + 12.4) = 1.9

4.7y - 2.5y - 12.4 = 1.9

2.2y = 1.9 + 12.4

2.2y = 14.3

y = 14.3/2.2

y = 6.5

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(8.3 - к) * 4.7 = 5.64

8.3 - к = 5.64 / 4.7

8.3 - к = 1.2

к = 8.3 - 1.2

к = 7.1

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(9.2 - m) * 3.2 = 16

9.2 - m = 16 / 3.2

9.2 - m = 5

m = 9.2 - 5

m = 4.2