# I need my $$\sqrt5$$ index 2

Geometry Level 5

Find the sum of the five diagonals of a cyclic pentagon with circumradius 85 and lengths 72, 80, 26, 154, and 136. Let this be $$\dfrac ab$$, where $$a$$ and $$b$$ are coprime positive integers. Find $$a+b$$.

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