Inscribed angles vs Central angles

Front

What is an inscribed angle?

Back

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.

Front

What is a central angle?

Back

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.

Front

How do you calculate the measure of an inscribed angle?

Back

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

Front

How do you calculate the measure of a central angle?

Back

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

Front

What is the relationship between an inscribed angle and its intercepted arc?

Back

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

Front

What is the measure of a minor arc?

Back

A minor arc measures less than 180 degrees.

Front

What is the measure of a major arc?

Back

A major arc measures more than 180 degrees.

Front

If the measure of arc AD is 38°, what is the measure of the inscribed angle that intercepts arc AD?

Back

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

Front

If the measure of a central angle is 80°, what is the measure of the intercepted arc?

Back

The measure of the intercepted arc is also 80°.

Front

What is the sum of the measures of the angles around a point?

Back

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