Question 1132292
square made by joining the mid points of the adjacent sides of a square of side "a":
a/2 = side of circumscribing square
sqrt[(a/2)^2 + (a/2)^2] = any one of the sides of the circumscribing square: E F, F G, G M, H E.
Any one of these, let's take F G, is the diameter of the circle circumscribed by the square
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Side of circumscribing square = diameter circle
To solve from here, apply Heron's formula, then a little trigonometry, and you're done. Here is a picture I made you to help you:
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