Предмет: Геометрия, автор: a100498

2.112. Отрезок AD является биссектрисой треугольника ABC. Найдите отрезки BD и CD, если AB=14 см, ВС=20 см, АС=21 см.

Ответы

Автор ответа: MagdaSinger

3

Ответ:

АВ:АС=ВD:СD

ВD=x, CD=20-x

14/21=x/(20-x)

14(20-x)=21x

280-14x=21x

35x=280, x=8см=ВD

СD=20-x=12 см

Объяснение:

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