MathDB
XY/YZ is independent of the position of X.

Source: Canada MO 2003

July 25, 2004
ratiogeometry solvedgeometry

Problem Statement

Three fixed circles pass through the points AA and BB. Let XX be a variable point on the first circle different from AA and BB. The line AXAX intersects the other two circles at YY and ZZ (with YY between XX and ZZ). Show that the ratio XYYZ\frac{XY}{YZ} is independent of the position of XX.