Предмет: Геометрия, автор: kostaja401

основание треугольника проходящее через цент окружности равно 5, радиус вписанной в треугольник окружности равен 2, найти площадь треугольника

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Ответы

Автор ответа: liftec74
0

Ответ: такой треугольник не существует

Объяснение:

Так как О∈АС, то ∡АВС=90° (угол опирается на диаметр окружности равен 90°).

=> ΔАВС -прямоугольный  АС=5 см -гипотенуза

Примем ВС=х  АВ=у

Расстояние от В до точек касания со вписанной окружностью равно r=2. => Расстояние от С до точек касания равно  х-2.

Расстояние от А до точек касания равно  у-2.

=> AC=(x-2)+(y-2)  =x+y-4 =5 => x+y=9 (1)  

AC²=x²+y²    (2) - т.Пифагора

Решаем полученную систему уравнений

x=9-y

(9-y)²+y²=5²

81-18y+y²+y²=25 => 2y²-18y+56=0

y²-9y+28=0

D=81-28*4 <0 =>корней нет=>такой треугольник не существует

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