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What is the area of a regular pentagon with a radius of 6 cm?

User Dpjanes
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1 Answer

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Answer:

85.6 cm^2

Explanation:

The area of the central triangle bounded by each of the sides can be computed as ...

A = (1/2)r²sin(α) . . . . where α is the central angle, 360°/5 = 72°

There are 5 such triangles, so the area of the pentagon is ...

A = (5/2)(6 cm)²sin(72°) ≈ 85.595 cm²

The area of the regular pentagon of radius 6 cm is about 85.6 cm².

What is the area of a regular pentagon with a radius of 6 cm?-example-1
User Monte Hurd
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