Предмет: Алгебра, автор: Neeess

1. Решите систему уравнений методом подстановки.

7x-2y=15

2x+y=9

P.S. должна быть скобка слева.

Ответы

Автор ответа: VVion

0

из 2-го

y = 9-2x

7x -2(9-2x)=15

7x-18+4x=15

11x=33

x = 3

6+y=9

y =3

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