Chapter+9trol

**9.1 CHORDS AND ARCS**

Objectives : 1. Define a circle and its associated parts, and use them in constructions 2. Define and use the degree measure of arcs. 3. Define and use the length measure of arcs. 4. Prove a theorem about chords and their intercepted arcs


 * __DEFINITIONS AND BLUE BOXES:__**

plane known as the center of the circle. the center of the circle. lie in the interior of the angle is th intercepted arc of the central angle. angle. The degree measure of a major arc is 360 degrees minus the degree measure of its minor arc. The degree measure of a semicircle is 180 degrees. length, //l//, of the arc is given by the followin: L=m/360(2*3.14*//r//)
 * CIRCLE-** a circle is the set of all points in a plane that are equidistant from a given point in the
 * RADIUS CHORD-** is a segment whose endpoints line on a circle.
 * DIAMETER-** is a chord that contains the center of a circle.
 * CENTERAL ANGLE-** a central angle of a circle is an angle in the plane of a circle whose vertex is
 * INTERCEPTED ARC-** An arc whose endpoints lie on the sides of the angle and whose other points
 * DEGREE MEASURE OF ARCS-** The degree measure of a minor arc is the measure of its central
 * ARC LENGTH-** if //r// is the radius of a circle and //m// is the degree measure of an arc of the circle, then the