Предмет: Геометрия, автор: importline

Решите пожалуйста срочно кто может
Знайдіть площу рівностороннього трикутника, якщо радіус вписаного в нього кола дорівнює 2

Ответы

Автор ответа: nabludatel00
0
рисунок рисовать не буду. грузить формулами не буду.

равносторонний- все стороны равны, все углы по 60, все медианы=высотам=биссектрисам.
значит пересечение медиан - центр впис. окр. пересеч. медиан делит их в отношении 2:1 считая от вершины. значит, медиана(и высота тоже) будет равна 3 радиуса, т.е. 6
а из прямоуг. треугольника, образованного стороной(гипотенуза) высотой и половиной стороны (катеты) сторона будет = 
а=6/sin60=12/√3

S=a*h/2=12/√3*6/2=12√3
Автор ответа: nabludatel00
0
я так понял, что все понятно.?..
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