Предмет: Алгебра, автор: dimabratko9

Решите систему уравнений методом сложения:
{7x+5y=19
{4x-3y=5
Помогите! ( это одна система )

Ответы

Автор ответа: Пеппер
1

{7x+5y=19  (умножим на -4)

{4x-3y=5 (умножим на 7)

-28х-20у=-76

28х-21у=35

-41у  =  -41;  у=1

4х-3=5;  4х=8;  х=2;

Ответ: (2; 1)

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