Треугольник – это три точки, не лежащие на одной прямой, соединенные отрезками. При этом точки называются вершинами треугольника, а отрезки – его сторонами.
Отрезок, соединяющий середины двух его сторон называется средней линией треугольника. Средняя линия треугольника параллельна третьей стороне, а ее длина равна половине длины этой стороны:
А1В1 = АВ / 2;
А1В1 = 8 / 2 = 4 см;
В1С1 = ВС / 2;
В1С1 = 5 / 2 = 2,5 см;
А1С1 = АС / 2.
А1С1 = 7 / 2 = 3,5 см.
Периметром треугольника есть сумма всех его сторон:
Р1 = А1В1 + В1С1 + А1С1;
Р1 = 4 + 2,5 + 3,5 = 10 см.
Ответ: периметр треугольника ΔА1В1С1 равен 10 см.
Автор:
jaslenebarberДобавить свой ответ
11 класс английский язык
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