In the below figure, EB is tangent to the circle with center C at the point B. If EC is equal to the diameter of the circle, find the measure of angle BAD in degrees.
m angle EBC = 90 deg because the question says EB is tangent to circle
cos (angle ECB) = radius/(2 * radius) = 1/2
m angle ECB = 60 deg
Therefore m angle BAD = 60 deg / 2 = 30 deg :D