Inscribed angles vs Central angles

An inscribed angle is an angle formed by two chords in a circle which have a common endpoint. The vertex of the angle is on the circle.

A central angle is an angle whose vertex is at the center of the circle and whose sides are radii that extend to the circle.

The measure of an inscribed angle is half the measure of the intercepted arc.

The measure of a central angle is equal to the measure of the intercepted arc.

The inscribed angle is always half the measure of its intercepted arc.

A minor arc measures less than 180 degrees.

A major arc measures more than 180 degrees.

The measure of the inscribed angle is 19° (half of 38°).

The measure of the intercepted arc is also 80°.

The sum of the measures of the angles around a point is 360°.