MathDB
A, B, and Q lie on a circle with center T

Source: Finland 2017, p5

September 8, 2019
circleCircumcenterdiametergeometry

Problem Statement

Let AA and BB be two arbitrary points on the circumference of the circle such that ABAB is not the diameter of the circle. The tangents to the circle drawn at points AA and BB meet at TT. Next, choose the diameter XYXY so that the segments AXAX and BYBY intersect. Let this be the intersection of QQ. Prove that the points A,BA, B, and QQ lie on a circle with center TT.