Предмет: Геометрия, автор: vitaliikkk

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Два кола мають внутрішній дотик. Відстань між їхніми центрами дорівнює 15 см. Знайдіть радіуси цих кіл, якщо вони відносяться як 4:7

Ответы

Автор ответа: zmeura1204

Відповідь:
20см; 35см

Розв'язання:
R-r, внутрішній дотик.
Нехай радіус меншого кола 4х, а більшого 7х.
Рівняння:
7х-4х=15
3х=15
х=15/3
х=5
5*4=20см радіус меншого кола
5*7=35см радіус більшого кола.

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