Предмет: Математика, автор: nastya6269

на двух полках- 39 книг если с первой полки переставить на вторую 4 книги то на первой полке станет в 2 раза больше чем на второй сколько книг на каждой полке?

Ответы

Автор ответа: RuleruWu

Пусть на первой х книг, а на второй полке у книг Тогда х-4=2(у+4) х-4=2у+8 х=2у+12 На первой х, на второй у, вместе на них 39 х+у=39 2у+12+у 3у+12=39 3у=27 у=9 х=30.

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