Предмет: Алгебра, автор: madinatyrzanova47

помогите с 3 заданием, пожалуйста ​

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Автор ответа: udushsbnej
0
Обозначим катеты прямоугольного треугольника (AB) и (BC) (где (AB) — гипотенуза) как (a) и (b) соответственно. Пусть (CD) — высота, проведенная к гипотенузе (AB).

Согласно условию задачи, (CD) делит гипотенузу на два отрезка, длиной 9 см и 25 см.

Итак, (AD = 9) см и (DB = 25) см.

Применим подобие треугольников
(ABC) и (CDB):

CD/BC = AD/AB

Подставим известные значения:

CD/BC = 9/b

Теперь найдем (BC):

BC = b/9*CD

Аналогично для треугольника (ABC) и отрезков (CD) и (DB):

C/AB =BC/BD

Подставим значения:

CD/AB =CD/a + b

Теперь найдем (AB):

AB = a + b/CD*CD = a + b

Таким образом, мы имеем систему уравнений:

BC = b/9*CD
AB = a + b

С учетом известных длин отрезков (AD) и (DB), можно решить эту систему уравнений, а затем найти периметр треугольника:

P = a + b + AB
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