Предмет: Математика, автор: Veronar

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У прямоугольника периметр которого равен 30м ширина в 4 раза короче длины найдите площадь прямоугольника.
И вторая
Периметр (сумма для сторон) прямоугольника 28 см одна сторона прямоугольника равна 6 см найдите площадь прямоугольника)

Ответы

Автор ответа: miron2077
7

х ширина

4х длина

30:2=15 см полупериметр (ширина + длина)

х+4х=15

5х=15

х=3см ширина

3*4=12см длина 12*3=36см² площадь

28:2=14см полупериметр

14-6=8см вторая сторона

6*8=48см² площадь

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