Предмет: Математика, автор: epolovinkina654

сроооооочно пожалуйста!!!!!!!!!!!!
В параллелограмме ABCD диагонали равны. Найдите величину угла BCA, если ∠ВАС = 50°

Ответы

Автор ответа: ildar502020

1

Ответ: 40°.

Пошаговое объяснение:

Диагонали равны только в прямоугольнике. Следовательно ∠В=90°.

В Δ сумма углов равна 180°.

∠ВАС+∠В+∠ВСА=180°.

∠ВСА=180°-(∠ВАС+∠В)=180°-(90°+50°)=180°-140°=40°.

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