A very interesting problem, took me some time to solve it, the total magnitud of the side length is 4 since 2+SQRT(2) is + & - (1.4142) so 2+ SQRT(2) + ( - SQRT (2) = 4 this give the diameter of the a circle that cover 2R + 2r and haft of it is the radius (R+r) so the answer is 2. At first you will take the sides to be 2 + 1.4142 but this is only part of the "picture" you will have to ADD the second component in the original question (2 - 1.4142) = 0.5858

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