Question

Решите пожалуйста 7-8 класс Не на ЛИСТКЕ!

Answer 1

1.

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(x - 2y) + (x + 2y) = 7 + 1

-4y = 8

y = 8 : (-4)

y = -2

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x - 2 * (-3) = 7

x + 4 = 7

x = 7 - 4

x = 3

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Ответ: (-2; 3).

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2.

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(х + 3у) - (х+2у) = 7 - 5

у = 2

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х + 3 * (2) = 7

х + 6 = 7

х = 7 - 6

х = 1

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Ответ: (2; 1).

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3.

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(4х - 6у) + 2 * (5х + 3у) = 26 + 2 * 1

14x = 28

x = 28 : 14

x = 2

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4 * 2 - 6y = 26

8 - 6y = 26

-6y = 26 - 8

-6y = 18

y = 18 : (-6)

y = -3

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Ответ: (2; -3).

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4.

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5 * (3x - 2y) + 2 * (2x + 5y) = 5 * 5 + 2 * 16

19x = 57

x = 57 : 19

x = 3

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3 * 3 - 2y = 5

9 - 2y = 5

7y = 5

y = 7 - 5

y = 2

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Ответ: (3; 2).

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