Предмет: Геометрия, автор: мастихина

вычислить площадь боковой и полной поверхности правильной треугольной пирамиды, все ребра которой равны по 20 см.

Ответы

Автор ответа: tuberculos07

площадь боковой поверхности состоит из трех равносторонних треугольников со сторонами по 20см. Sбп =3 sqrt(3)*a^2/4 = 300sqrt(3)

полная включает в себя еще один треугольник - основание. S=400sqrt(3)

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