Angle Formed by a Chord and a Tangent
by Sofia Arcoy
Drag Point B or C to find out the relationship between angle CBD and arc CB.
Upon observation, you will see that Chord CB and Tangent BD create an angle that intercepts arc CB. And this formed angle (Angle CBD), measures half of arc CB, the arc it intercepts. (Indicated in central angle CAB is the measurement of arc CB)