Предмет: Математика, автор: логл

15x+20y=675 пожалуйста помогите

Ответы

Автор ответа: таня90

15х+20у=675/5

3х+4у=135

4у=135-3х

у=135-3х/4

3х+4(135-3х)/4=135

12х+135-3х=540

9х=405

х=405:9

х=45

3*45+4у=135

4у=135-135

4у=0

у=0:4

у=0

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