Предмет: Математика, автор: dachunya97

из пункта а в пункт в, расстояние между которыми 100 км, одновременно выехали мотоциклист и велосипедист. мотоциклист едет на 30 км/ч быстрее, сем велосипедист, и приезжает в пункт в на три часа раньше. найдите скорость велосепедиста

Ответы

Автор ответа: Элиzzzочка

100/x - 100/x+30 = 3

после пробразований получается:

100x+3000-100x=3x(в квадрате)+90x

3x(в квардате) + 30x -1000 = 0

x1 = - 20 ( не подходит по смыслу)

x2 = 50

Ответ 50 км/ч

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