Circle Theorems

Front

What is the measure of an angle formed by two intersecting chords in 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

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

Back

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

Front

What is a sector in a circle?

Back

A sector is a region of a circle bounded by two radii and the arc between them.

Front

What is the difference between a secant and a tangent?

Back

A secant intersects a circle at two points, while a tangent touches the circle at exactly one point.

Front

How do you calculate the measure of an angle formed by a tangent and a chord?

Back

The measure of the angle is equal to half the measure of the intercepted arc.

Front

What is the relationship between the angles formed by two intersecting chords?

Back

The angles are equal to half the sum of the measures of the arcs intercepted by the angle.

Front

What is the formula for finding the measure of an angle formed by two secants?

Back

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

Front

What is the definition of a circle's arc?

Back

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

Front

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

Back

The length of an arc can be found using the formula: (θ/360) * 2πr, where θ is the central angle in degrees and r is the radius.

Front

What is the central angle of a circle?

Back

A central angle is an angle whose vertex is at the center of the circle and whose sides intersect the circle.