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В окружности проведены 2 хорды AB и CD, пересекающиеся в точке K. KC = 6 см. AK = 8см, BK+DK=21 см. Найдите длины BK и DK.
Ответы 1
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есть такое свойство про пересекающиеся в окружности хорды, произведени отрезков одной хорды равно произведению отрезков другой.
АК*KB=CK*KD
AK=8
CK=6
BK=x
KD=21-x
6(21-x)=8x
126-6x=8x
14x=126
x=9
BK=9
KD=12
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Автор:
aries - 6 лет назад
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