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Из точки O, не принадлежащей ни одной
из двух параллельных плоскостей, проведены три прямые, пересекающие плоскости
соответственно в точках A, B, C и A1, B1, C1. Найдите BC, если OA = a, AA1 = b, B1C1 = c.
Ответы 1
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Плоскости параллельны,значит сохраняется подобие фигур и пропорциональность отрезков.OA = a, AA1 = b, B1C1 = c.ОА/ОА1=ВС/В1С1ВС=а*с/(а+b)
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Автор:
kysonwaxv - 5 лет назад
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