Geometry 11-4 Inscribed Angles Inscribed angle- an angle whose vertex is on the circle. Intercepted arc- the arc in between the sides of the angle AC is the intercepted arc
Theorem 1 The inscribed angle is half the measure of the intercepted arc. 100° 50° A B C
Example Find each measure.
Example Find the value of a.
Example Determine the value of x. (3x – 20)° x°
Theorem 2 If a quadrilateral is inscribed in a circle, then its opposite angles are supplementary. A B C D
Example Find the value of b.