Предмет: Математика, автор: 89225591787

периметр квадрата равен 80см. вычислить площадь квадрата.

Ответы

Автор ответа: vmaluga2011

80 см : 4 = 20 см - сторона квадрата
20 см * 20 см = 400 см2 = 4 дм2

Автор ответа: vmaluga2011

А сразу написать, что в дециметрах?

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