Basic Angles and Arcs of Circles

Front

What is the definition of a circle?

Back

A circle is a set of points in a plane that are equidistant from a fixed point called the center.

Front

What is the measure of a right angle?

Back

90 degrees.

Front

What is a minor arc?

Back

A minor arc is an arc that is smaller than a semicircle.

Front

What is the formula to find the measure of an angle outside a circle?

Back

(1/2)(arc1 - arc2), where arc1 and arc2 are the measures of the intercepted arcs.

Front

What is the measure of a semicircle?

Back

180 degrees.

Front

What is the relationship between the central angle and the arc it intercepts?

Back

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

Front

What is the definition of a major arc?

Back

A major arc is an arc that is larger than a semicircle.

Front

How do you find the circumference of a circle?

Back

Circumference = 2πr, where r is the radius of the circle.

Front

What is the definition of an inscribed angle?

Back

An inscribed angle is an angle formed by two chords in a circle which have a common endpoint.

Front

What is the measure of an inscribed angle?

Back

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