Предмет: Геометрия, автор: viatg

У трикутнику АВС проведено медіану ВО завдовшки 6 см і висоту ВD. Кут DВО між ними дорівнює 30°. Знайдіть основу АС якщо DС=5см.

Ответы

Автор ответа: 11ReLaX11
0
∆АDC:
Т.к. угол D=30°, а В=30°, то по свойству стороны, лежащей напротив угла 30° в прямоуг.треуг.: DO=1/2 OB=3см
ОС=DC-DO=2см
т.к. ВО медиана, то ОС=АО=2см
АС=ОС+АО=2+2=4 см
Автор ответа: viatg
0
Ето не правильно
Автор ответа: viatg
0
А нужно правильно
Автор ответа: 11ReLaX11
0
почему же не правильно?
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