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Not another geometry, going to bed

Geometry Level 2

The number of diagonals of a regular polygon is 27. Then, each of the interior angles of the polygon is?

150 100 140 120

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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View solutions

by Jayesh Agrawal

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