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A regular heptagon with 7 sides is inscribed in a circle with radius 10 millimeters. What is the area of the figure? 273.641 mm.2 234.549 mm.2 39.092 mm.2 321.311 mm.2

User Vlado
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2 Answers

18 votes
18 votes

Answer:

273.641 mm²

Explanation:

User Amo
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14 votes
14 votes

Given:

A regular heptagon with 7 sides is inscribed in a circle.

The radius is 10 mm.

The inscribed angle in the regular heptagon is 51.43 degrees.

Consider,


\begin{gathered} a^2=10^2+10^2-2(10)(10)\cos 51.43^(\circ) \\ a^2=200-200(0.6235) \\ a=8.68 \end{gathered}

The area of the heptagon is,


\begin{gathered} A=(7)/(4)a^2\cot ((180^(\circ))/(7)) \\ =(7)/(4)(8.68)^2\cot ((180^(\circ))/(7)) \\ =273.7\operatorname{mm} \end{gathered}

Answer: option a) 273.641 mm² ( approximately)

A regular heptagon with 7 sides is inscribed in a circle with radius 10 millimeters-example-1
User Zett
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