1971 Canadian MO Problems/Problem 1

Problem

is a chord of a circle such that and Let be the center of the circle. Join and extend to cut the circle at Given find the radius of the circle

Solution

First, extend to meet the circle at Let the radius be Applying power of a point, and Hence,

1971 Canadian MO (Problems)
Preceded by First question	1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 •	Followed by Problem 2