Предмет: Математика, автор: ForceMaestro

Дана трапеция.
AB=CD
угол CDA равен 30 градусов
CD=10
BC=8
Найти площадь трапеции.

Гимнаст44rus: AB и CD это основания?

Ответы

Автор ответа: Аноним
1
С треугольника CDK(\angle CKD = 90а):\,\,KD=CD\cdot \cos30=5 \sqrt{3}
CK=CD\cdot \sin30=5

основания AD = BC + 2 KD = 8+10√3

S= \frac{8+10 \sqrt{3}+8 }{2} \cdot5=40+25\sqrt{3}

Ответ: 40+25\sqrt{3}.
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