Предмет: Алгебра, автор: fendrikovaviktoria33

Помогите пожалуйста
Объясните как решить эту систему линейных уравнений
4x-7y=30
4x-5y=90

Ответы

Автор ответа: Аноним

1

4х-7у=30 >> 4х=30-7у

4х-5у=90 >> 30-7у-5у=90 >> -12у=60 >> у=-5

4х=30-7×(-5) >> 4х=65 >> х=16,25

ответ: (16,25;-5)

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