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imc

geometry intermediate

Problem

Four circles of radius are each tangent to two sides of a square and externally tangent to a circle of radius , as shown. What is the area of the square?
problem
(A)
(B)
(C)
(D)
Solution
We draw the diagonal of the square. This diagonal yields . We know that the side length in terms of the diagonal is , so our side length is . However, we are trying to look for the area, so squaring yields
Final answer
B