Четырехугольник АВСD вписан в окружность. Докажите, что угол А +угол С =угол В +угол D

Четырехугольник АВСD вписан в окружность. Докажите, что угол А +угол С =угол В +угол D
- Предмет:
  Геометрия
- Автор:
  leftycharles
- 5 лет назад

Ответы 1

угол A- вписаннвй в окр. угол,он измеряется1/2 дуги BCD на которую опираетсяуголC измеряется 1/2 дуги DABдугаDAB+дугаBCD это 360 градусов(полная окружность)уголA+уголC=1/2×360=180 градусовтакже два других угласледовательно уг.A+уг.C=уг.B+уг.D=180 градусов
- Автор:
  petercantu
- 5 лет назад
- 0
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Четырехугольник АВСD вписан в окружность. Докажите, что угол А +угол С =угол В +угол D

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