Structure of a good film review Read the introduction and fill in the gap with the correct word. The first letter of the word is given.

The story is sin Middle-earth sixty years before the main events of The Lord of the Rings.

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Геометрия: Structure of a good film review Read the introduction and fill in the gap with the correct word. The first letter of the word is given.  The story is sin Middle-earth sixty years before the main events of The Lord of the Rings. Back Check ​

AD1628 · Accepted Answer

Проведем радиус СО, точку пересечения назовем F, рассмотрим ΔCOF:

sin∠OCF=OF/OC=r/2:r=1/2, OCF=30°, ∠COF=60°

Соединим С и B, ΔCOB:

OC=OB=r, ΔCOB равнобедренный

∠COB=∠CBO=60° ⇒ ∠OCB=60°, ΔCOB - равносторонний

СF - биссектриса, ∠OCF=OBF=60°/2=30°

∠C опирается на диаметр ⇒ ∠С=90°, ∠ACF=∠C-∠FCB=∠C-∠OCF=90°-30°=60°

Хорда, перпендикулярная диаметру, проходит через ее середину ⇒ FC=FD=8/2=4см, АF - высота, медиана и биссектриса ⇒ ΔACD -равнобедренный

∠ADC=∡ACD=60°, ∠A=60° ⇒ ACD - равносторонний

P=CD+AD+AC=3CD=3*8 см=24 см

ответ: 24 см.

Structure of a good film review Read the introduction and fill in the gap with the correct word. The first letter of the word is given. The story is sin Middle-earth sixty years before the main events of The Lord of the Rings.BackCheck​

MOGZ ответил

Structure of a good film review Read the introduction and fill in the gap with the correct word. The first letter of the word is given.

The story is sin Middle-earth sixty years before the main events of The Lord of the Rings.

Back

Check