Let PQ be a diameter of a circle,
A be a point on line PQ such that P lies between A and Q,
T be a point on the circle such that line AT is tangent to the circle,
B be the point on line QT such that line BP is perpendicular to line PQ, and
C be the point on line PT such that line CQ is perpendicular to line PQ.
Prove that points A, B, and C are collinear.