Question

Решите систему уравнений

Answer 1

x - 3y = 5 - 0,2x - 20y

0,5x - y - 2 = 2 - x - 20y

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x + 0,2x = 5 - 20y + 3y

0,5x + x = 2 + 2 + y - 20y

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1,2x = 5 - 17y

1,5x = 4 - 19y

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1,2x = 5 - 17y

x = 8/3 - 38/3y

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1,2(8/3 - 38/3y) = 5 - 17y

x = 8/3 - 38/3y

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16/5 - 76/5y = 5 - 17y

x = 8/3 - 38/3y

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-15,2y + 17y = 5 - 3,2

x = 8/3 - 38/3y

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1,8y = 1,8

x = 8/3 - 38/3y

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y = 1

x = 8/3 - 38/3 = -30/3 = -10

Ответ: x = -10, y = 1