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The radius of a circle

Geometry Level 2

The four circles of same radius are included into right triangle as shown in the above figure. What is the radius of a circle?

4 cm 5 cm 2 cm 8 cm

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 Sensen Liong

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