Помогите решить задачу... Отрезок BD - диаметр окружности с центром 0. Хорда AC делит

Помогите решить задачу...
Отрезок BD - диаметр окружности с центром 0.
Хорда AC делит пополам радиус OB и перпендикурярна к нему. Найдите углы четырёхугольника ABCD и градусные меры дуг AB, BC, CD, AD.
- Предмет:
  Геометрия
- Автор:
  ruffevowx
- 6 лет назад

Ответы 1

З рівності трикутників АОС і АВС випливає що кут АОС= кут АВСКут ВАД =кут ВСД=90° оскільки ВД діаметрКут АВС=кут АОС=2*кут АДСКут АДС+кут АВС=360-90-90=180ОтжеКут АДС +2* кут АДС=180Кут АДС=60°Кут АВС=2*60=120°. Дуга ВА=дуга ВС=60°, Дуга АД=Дуга СД=(360-2*60)/2=120
- Автор:
  donovansu7z
- 6 лет назад
- 0
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LONDON UNDERGROUND
The London Underground (it is often called the Tube) is the oldest metro in the world. It has been used for passenger transporting since 1863. Nowadays the London Underground is the most popular means of city transport because it is relatively cheap, convenient, quick and safe. Its length is about 400 km. Every day the Tube carries over 2.5 million passengers. The total number of passengers carried by the Underground each year is enormous and it is constantly growing.
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9. Are there twelve Underground lines in London?
10. Do all the underground lines have their own color?
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