Предмет: Геометрия, автор: Kr0ha

Дано: SABCD- правильная четырёхугольная пирамида, SH - апофема , SH=5дм , AD-6дм . Найти объём пирамиды.
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Автор ответа: Аноним
0
V = 1/3*S осн.*SO
S осн. = 36 дм² Ищем высоту SO
Δ SOD
SO² = 25 - 9 = 16
SO = 4
V = 1/3 * 36*4 = 48
Автор ответа: massg
0
основание квадрат, высота пирамиды по теореме Пифагора

=√(25 - 9) = 4

объем = 1/3 * 6*6*4 = 48 куб.дм
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