Central Angles and Arc Measures 1

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

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 its intercepted arc.

Front

If the measure of arc AB is 90 degrees, what is the measure of the central angle AOB?

Back

The measure of the central angle AOB 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 angle JNM is 159 degrees, what is the measure of arc JM?

Back

The measure of arc JM is also 159 degrees.

Front

What is the measure of arc KL if the central angle is 159 degrees?

Back

The measure of arc KL is 159 degrees.

Front

How do you find the measure of an angle formed by two chords that intersect inside a circle?

Back

The measure of the angle is equal to half the sum of the measures of the arcs intercepted by the angle.

Front

What is the measure of angle UXV if the intercepted arc is 144 degrees?

Back

The measure of angle UXV is 72 degrees.