Central and Inscribed Angles

Front

What is a central angle?

Back

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

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

How do you find the measure of a central angle?

Back

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

Front

How do you find the measure of an inscribed angle?

Back

The measure of an inscribed angle is half the measure of the arc it intercepts.

Front

What is the relationship between a central angle and an inscribed angle that intercept the same arc?

Back

The central angle is twice the measure of the inscribed angle.

Front

If the measure of arc AB is 68 degrees, what is the measure of the inscribed angle that intercepts arc AB?

Back

34 degrees.

Front

If the measure of arc FH is 140 degrees, what is the measure of the central angle that intercepts arc FH?

Back

140 degrees.

Front

What is the measure of angle K if angle M is 100 degrees and they are inscribed angles intercepting the same arc?

Back

Angle K measures 50 degrees.

Front

If an inscribed angle measures 52 degrees, what is the measure of the arc it intercepts?

Back

104 degrees.

Front

What is the formula to calculate the measure of an inscribed angle?

Back

Measure of inscribed angle = 1/2 * Measure of intercepted arc.