Central Angles and Arc Measures

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 extend to the circumference.

Front

How do you calculate the measure of an arc?

Back

The measure of an arc is equal to the measure of the central angle that subtends the arc.

Front

What is the relationship between a central angle and its intercepted arc?

Back

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

Front

If the measure of a central angle is 90 degrees, what is the measure of the intercepted arc?

Back

The measure of the intercepted arc is also 90 degrees.

Front

What is the formula for finding the length of an arc?

Back

Arc length = (θ/360) * 2πr, where θ is the central angle in degrees and r is the radius.

Front

What is the measure of a semicircle?

Back

The measure of a semicircle is 180 degrees.

Front

If the measure of arc KL is 159 degrees, what is the measure of the central angle that subtends it?

Back

The measure of the central angle that subtends arc KL is also 159 degrees.

Front

What is the measure of arc FD if the central angle is 124 degrees?

Back

The measure of arc FD is 124 degrees.

Front

If the measure of arc DCF is 236 degrees, what is the measure of the central angle?

Back

The measure of the central angle is 236 degrees.

Front

What is the measure of arc PQ if the central angle is 71 degrees?

Back

The measure of arc PQ is 71 degrees.