1. ARCS AND CENTRAL ANGLES
Arc and arc measure
Minor Arc
Major Arc
Semicircle
Adjacent arcs

2. VERTEX OF THE CENTRAL ANGLE IS THE CENTER OF THE CIRCLE
Central Angles
Circle B, Angle ABC A
VERTEX OF THE CENTRAL ANGLE IS THE CENTER OF THE CIRCLE C B

3. ARCS AND ARC MEASURE Arc AC and Central Angle ABC
Arc: part of a circle
Arcs and central angles are measured in degrees A
Arc AC and
Central Angle ABC
have the same measure C B

4. MORE ABOUT ARCS Semicircle: arc PSR measure of exactly 180
Minor Arc: arc AC
measures less than 180
Major Arc: arc DEF measures greater than 180 F C A D T . E B
Semicircle: arc PSR
measure of exactly 180 . . S Q . P R

5. Adjacent arcs share a common endpoint m arc AD + m arc DP equals
m arc AP D A P G