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.

(In reply to counterproof (maybe) by Daniel)

"since ABQ is a right angle ..."

ABQ is not a right angle.

Click here.

Edited on December 12, 2009, 12:28 pm

Posted by Charlie on 2009-12-12 12:16:10