Предмет: Геометрия, автор: zagurska13

7x + 2y = 5,
7x – 3y = 45.
допоможіть срочно!!!​

Ответы

Автор ответа: Пирожок18
2

Ответ:

система кажется уравнения. 7х=5-2у ; x=5/7-2/7y; (подставляем во второе уравнение 7х-3у=45) . 7(5/7-2/7y) -3у=45; 5-2y-3y=45; -5y=40; y=-8;

7x=5-2*(-8); 7x=21; x=3.

x=3

y=-8

Объяснение:

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