Предмет: Геометрия, автор: Аноним

1)Через вершину В квадрата ABCD проведена Прямая BH перпендикулярна к его плоскости. Найдите длину отрезка BH если наклонная HC=8см а сторона AB=6см
2)Прямые а и б параллельны. Прямая а перпендикулярна к плоскости а, прямая d лежит в плоскости а.Найти угол между прямыми а и d, а и b

Ответы

Автор ответа: кот666666

1)Т.к. ABCD - квадрат, то AB=BC=6.
Т.к. BH перпендикулярно ABCD, то BH перпендикулярно BC, значит треугольник BHC - прмяоугольный. По теореме пифагора найдем BH =√28

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