Предмет: Геометрия, автор: Аноним

3. Найдите площадь параллелограмма, и 10 см, а угол между ними равен: а) 30º: б) 45º; в) 60°. если его стороны равны 8 см 93​

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Ответы

Автор ответа: zmeura1204
2

Ответ:

а) S=40см²

б) S=40√2см²

в=40√3см²

Объяснение:

Площадь параллелограмма равна произведению двух сторон на синус угла между ними!

S=a*b* sin∠(ab);

а=8см; b=10см

a) ∠(аb)=30°; sin30°=½

S=10*8*sin30°=80*½=40см²

б) ∠(ab)=45°; sin45°=√2/2

S=10*8*sin45°=80*√2/2=40√2 см²

в) ∠(ab)=60°; sin60°=√3/2

S=10*8*sin60°=80*√3/2=40√3см²

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zmeura1204: Добавила таблицу.
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