Предмет: Алгебра, автор: nastyaradetska

x + 2y = - 1
3x + 4y = - 7
СРОЧНООО ОТДАМ 40 БАЛООВ

Ответы

Автор ответа: windlele
1

Ответ:
x = -5, y = 2.

Объяснение:
Можно решить систему уравнений методом умножения первого уравнения на 3 и вычитания из второго уравнения:

x + 2y = -1  (умножаем на 3)

3x + 6y = -3

3x + 4y = -7

- (3x + 6y = -3)

------------

-2y = -4

y = 2

Теперь подставляем значение y в любое из уравнений и находим x:

x + 2y = -1

x + 2(2) = -1

x + 4 = -1

x = -5

Ответ: x = -5, y = 2.

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