Предмет: Математика, автор: Настя1644

от гнезда одновременно в противоположных направлениях полетели две ласточки.Через 20 секунд расстояние между ними было 680 м .Чему равна скорость одной из ласточек , если другая летела со скоростью 16 М/С

Ответы

Автор ответа: LisaTanyushka
4
1 вариант             
узнаем сколько метров пролетела первая ласточка
20*16=320
узнаем сколько вторая
680-320=360
узнаем ее скорость
360/20=18
 

2 вариант
пусть скорость второй ласточки Х м/с
20Х+20*16=680
20Х+320=680
 20Х=360 Х=18 м/с скорость второй ласточки
ответ: 18м/с.



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