Angles of Circles

Front

What is an angle in a circle?

Back

An angle in a circle is formed by two rays (sides of the angle) that meet at a common endpoint (the vertex) and are positioned at the center of the circle.

Front

What is the measure of a full circle in degrees?

Back

360 degrees.

Front

What is a diameter of a circle?

Back

A diameter is a straight line that passes through the center of the circle and connects two points on its circumference.

Front

What is the relationship between a diameter and a semicircle?

Back

A semicircle is half of a circle, formed by a diameter and the arc connecting its endpoints.

Front

How do you find the measure of an arc in a circle?

Back

The measure of an arc can be found using the central angle that subtends the arc; it is equal to the measure of the central angle.

Front

What is the measure of an arc when the central angle is 90 degrees?

Back

The measure of the arc is 90 degrees.

Front

What is the measure of an arc when the central angle is 180 degrees?

Back

The measure of the arc is 180 degrees, which represents a semicircle.

Front

If a diameter divides a circle into two equal parts, what are these parts called?

Back

These parts are called semicircles.

Front

What is the measure of a full arc in a circle?

Back

The measure of a full arc in a circle is 360 degrees.

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.