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40 votes
Identify the area of a regular decagon with side length 2 m rounded to the nearest tenth

User Thijs Koerselman
by
3.2k points

2 Answers

11 votes
11 votes

Answer:

A ≈ 30.8 m2

Explanation:

Identify the area of a regular decagon with side length 2 m rounded to the nearest-example-1
User Birk
by
2.9k points
15 votes
15 votes

Answer:

Area = 14.8

Explanation:

Area = 5/2 + a^2*sqrt(5 + 2 sqrt(5) )

This formula given the side length, calculates the area.

a = 2

Area = 2.5 + 2^2 * sqrt(5 + 2*sqrt(5) )

Area = 2.5 + 4 * sqrt(5 + 2*2.236)

Area = 2.5 + 4* sqrt(5+ 4.4721)

Area = 2.5 + 4*sqrt(9.4721)

Area = 2.5 + 4*3.0776

Area = 2.5 + 12.3107

Area = 14.8107

User KingRadical
by
3.0k points