Problem

Source: Finland 2012, Problem 1

Tags: ratio, quadratics, trigonometry, algebra, trig identities, Law of Cosines, geometry unsolved



A secant line splits a circle into two segments. Inside those segments, one draws two squares such that both squares has two corners on a secant line and two on the circumference. The ratio of the square's side lengths is $5:9$. Compute the ratio of the secant line versus circle radius.