2 ixl lessons for geometry|My essay solution

Central angles and arc measures:

• A central angle is an angle whose vertex is at the center of a circle and whose sides intersect the circle.
• The measure of a central angle is equal to the measure of the intercepted arc.
• An arc is a portion of the circumference of a circle.
• The measure of a minor arc is the measure of its central angle, and the measure of a major arc is 360 degrees minus the measure of its minor arc.
• The measure of a semicircle is 180 degrees, and the measure of a full circle is 360 degrees.