Предмет: Математика, автор: evgenyasheina08


За 2 год руху за течією та 3 год проти течії
човен проходить 43 км, а за 3 год руху за течією
та за 2 год проти течії він долає 47 км.
знайдіть швидкість течі.
​

Ответы

Автор ответа: volna7
7

Відповідь:

2 км/год.

Покрокове пояснення:

х - швидкість човна

у - швидкість течії

2х + 2у + 3х - 3у = 43

3х + 3у + 2х - 2у = 47

5х - у = 43

5х + у =47

Віднімемо від другого рівняння перше

2у = 4

у = 2 км/год.

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