Предмет: Геометрия, автор: Philllip

Основание равнобедренного треугольника равно 26 см, угол при основании равен 60 градусов. Найти периметр треугольника?

Ответы

Автор ответа: Miraveira
6
В равнобедренном треугольнике углы при основании равны, значит второй угол тоже 60
Сумма углов в треуг=18, третий угол тоже 60 
Все углы равны, значит треугольник правильный и все стороны равны
Р=26*3=78
Автор ответа: alinkabelka
2
Сумма углов в любом треугольнике равна 180 градусов,углы при основании равны,т.е.можно сделать вывод,что все углы по 60 градусов и треугольник равносторонний....отсюда следует,что все стороны у него по 26 см,а периметр-сумма всех сторон треугольника=> 26+26+26= 78 см
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