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The Pentagon

Geometry Level 3

Find the length of a side of a regular pentagon that is inscribed in a circle of radius 2.

\[5-\sqrt{5}\] \[\sqrt{10-2\sqrt{5}}\] \[1+\sqrt{5}\] none of the other three choices

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations,
examples, and problems from the community.

Used and loved by 4 million people

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including olympiad champions, researchers, and professionals.

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by Jaydee Lucero

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