Reflex Angles

Any angle that measures greater than 180° is call a Reflex Angle

Every angle has a reflex angle. The sum of an angle and its reflex angle make a full circle, or 360°.

Greek letters are used as variable for angle measurements.

The most commonly used Greek letters used for angle measures are the following:[br][math]\alpha[/math](alpha), [math]\beta[/math](beta), [math]\gamma[/math](gamma), [math]\delta[/math](delta)

By convention, we name and measure angles, especially angles within a circle, counterclockwise.

The direction, counterclockwise (or anti-clockwise), is generally "leftward" around the vertex.[br]For example: If point X was at the 12 on a clock and point Y was on the 3 on a clock and point W was at the center of the clock, then [math]\angle[/math]YWX would measure 90° and reflex [math]\angle[/math]XWY would measure 270°

Reflex Angle: use the figure to answer the questions below

1. Reflex Angles

If [math]\alpha[/math] = 57° what is [math]\beta[/math]?

33° 123° 213° 303° 57°

2. Reflex Angles

If reflex angle, [math]\angle[/math]CAB measures 221°, what is the m[math]\angle[/math]BAC?

131° 139° 311° 41°