Предмет: Алгебра, автор: lewwa79

Помогите найти, плиз, длину и ширину прямоугольного участка, обнесенный изгородью 200метров, площадь данного участка 2400кв.м

Ответы

Автор ответа: n1982

S=2400

Р=200

исходя из этих данных составим систему и решим пусть а-длина в-ширина

ав=2400

2а+2в=200

а=100-в (100-в)в=2400

в²-100в+2400=0

Д=10000-9600=400

в=60

в=40

подставим

а=100-60=40 и а=100-40=60

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