# The story of the green square.

Geometry Level 3

The green square in the diagram is symmetrically placed at the center of the circle. Four red equilateral triangles are drawn such that square $$ABCD$$ is formed. Let $$y,b,g,$$ and $$r$$ be the areas of the yellow, blue, green, and red regions, respectively.

If $$r=4\sqrt{3}$$, find $$y+g-b$$.

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