Предмет: Геометрия, автор: aquadefin

В окружности с радиусом равным 9 вписан равносторонний треугольник. Найдите площадь треугольника

Ответы

Автор ответа: Аноним

1

Радиус окружности равен (а√3/2)*(2/3)=9⇒а=27/√3=9√3

площадь равна а²√3/4=9*9*3*√3/4=60.75√3

Можно и по - другому. Если а - сторона треугольника, то по теореме синусов а/sin60°=2*9⇒а=18√3/2=9√3 .

а²√3/4=9*9*3*√3/4=60.75√3

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