Circles, Arcs, and Inscribed Angles

Front

What is 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 radius of a circle?

Back

The radius is the distance from the center of the circle to any point on its circumference.

Front

What is a diameter?

Back

The diameter is a line segment that passes through the center of the circle and has its endpoints on the circle. It is twice the length of the radius.

Front

What is a chord?

Back

A chord is a line segment whose endpoints lie on the circle.

Front

What is a secant?

Back

A secant is a line that intersects a circle at two points.

Front

What is a tangent?

Back

A tangent is a line that touches the circle at exactly one point.

Front

What is an arc?

Back

An arc is a portion of the circumference of a circle.

Front

What is an inscribed angle?

Back

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

Front

What is the relationship between an inscribed angle and its intercepted arc?

Back

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

Front

How do you find the measure of an angle formed by two secants?

Back

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