Предмет: Алгебра, автор: zaharnester

Моторний човен пройшов 48км за течією річки і повернувся назад, витративши на зворотній шлях на 1 год більше. Знайди швидкість течії, якщо власна швидкість човна дорівнює 14 км/год

Ответы

Автор ответа: sangers1959

Відповідь: швидкість течії 2 км/год.

Пояснення:

Нехай швидкість течії - х. ⇒

$\frac{48}{14-x} -\frac{48}{14+x}=1\\ 672+48x-672+48x=196-x^{2} \\x^{2} +96x-196=0\\D=10000;\sqrt{D} =100\\$

x₁=-98 ∉ x₂=2.

zaharnester: Вы - святой человек

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