Geometry question:
Take a circle A and circumscribe it by a square B.
Then circumscribe B by a circle C.

Prove that the area of circle C is exactly twice that of circle A.

Question

Geometry question:
Take a circle A and circumscribe it by a square B.
Then circumscribe B by a circle C. 

Prove that the area of circle C is exactly twice that of circle A.

anonymous · Answer

I am realizing that a square has 4 equal sides (s) and that the diagonal of a square is also (s). The area of a square is $$s^{2}$$ and that the perimeter is 4s. Also I realize by putting a diagonal on B, that I get two right triangles. Each of these has length s. I am thinking somehow that they pythagorean thm. could help with this problem, but not sure how. Any advice greatly appreciated.

anonymous · Answer

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