Предмет: Геометрия, автор: vadimbro741

Найдите угол CBA пожалуйста

Приложения:

Ответы

Автор ответа: 200720088
0

Ответ:

Дано:

DBC-треугольник

А-паралельно прямая

Угол DBA=40°

BAC-не известно

DA =AC

BC=BD

Объяснение:

Дальше не знаю

Автор ответа: ksusaguseva7
0

DB=BC=>∆DBC равнобедренный и угD= угС = 40°

Тк сумма углов треугольника равна 180°, то угВ= 180-(40+40)=100°

Тк DA=CA, то ВА - медиана равнобедренного треугольника

Тк медиана равнобедренного треугольника является ещё высотой и биссектрисой (в данном случае нужна биссектриса), то угDBA=угСВА

угDBA+угСВА=угВ, который равен 100°, значит угСВА = 100÷2=50°

ОТВЕТ: угол СВА равен 50°.

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