9.3+(WiBr56)

__Vocabulary__
 * inscribed angle**- is an angle whose vertex lies on a circle and whose sides are chords of the circle.

__Inscribed Angle Theorem__ The measure of an angle inscribed in a circle is equal to 1/2 the measure of the intercepted arc.

__Right - Angle Corollary__ If an inscribed angle intercepts a semicircle, then the angle is a right angle.

__Arc - Intercept Corollary__ If two inscribed angles intercept the same arc, then they have the same measure.



__Example__


 * In Circle p, measure of arc AB= 50 degrees and measure of angle CAD = 20 degrees**

//**measure of angle C**// Arc AB = 50 degree / 2 25 degrees

Angle A = 20 degrees x 2 40 degrees
 * //measure of arc CD//**

//**measure of angle B** Arc CD = 40 degrees / 2 20 degrees//

//**measure of angle E**// Arc AB (50 degrees) + arc CD (40 degrees), So Arc BC 90 degrees 50 degrees + 40 degrees +90 degrees = 180 degrees / 2 90 degrees

More Information http://www.regentsprep.org/Regents/math/geometry/GP15/PcirclesN.htm