Предмет: Алгебра, автор: kseniyaКсю

решите систему линейных уравнений

4х-7у=30

4х-5у=90

Ответы

Автор ответа: marlena
0

4х-7у=30

4х-5у=90

 

4х=30+7у

4х-5у=90

 

30+7у-5у=90

2у=60

у=30    х=(30+7*30)/4=60

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