Предмет: Геометрия, автор: potapov2018lexux

АВСD – трапеция с основанием АD =25см , диагонали АС и ВD пересекаются в точке О, ОА = 15см., ОС = 9см. Найти основание ВС.

Выберите один ответ:
10
5,4
4,5
15

Ответы

Автор ответа: VekaSolnce

ΔAOD подобен ΔBOC (по трем углам:∠DAC=∠BCA и ∠DBC=∠BDA -накрест лежащие, ∠DOA=∠BOC -вертикальные)
⇒AO:OC=AD:BC
15:9=25:BC
BC=25*9:15=15 см

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АВСD – трапеция с основанием АD =25см , диагонали АС и ВD пересекаются в точке О, ОА = 15см., ОС = 9см. Найти основание ВС. Выберите один ответ: 10 5,4 4,5 15

Ответы

АВСD – трапеция с основанием АD =25см , диагонали АС и ВD пересекаются в точке О, ОА = 15см., ОС = 9см. Найти основание ВС.

Выберите один ответ:
10
5,4
4,5
15