Chord properties  Circles
Chord properties
In a circle, when a line passes through the center of the circle and is perpendicular to a chord, the line will bisect the chord. In other words, the perpendicular bisector of a chord always passes through the center of the circle.
Basic concepts:
 Angles in a circle
 Tangent properties
 Circles and circumference
Lessons

3.
Below is a segment of a circle, and A is the center of the circle. The radius is 15 cm, BC is 7.5 cm, and DE is 24 cm.
Determine.