Angle Measures in Circles

Front

What is the measure of a full circle in degrees?

Back

360 degrees.

Front

What is a central angle in a circle?

Back

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

Front

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

Back

The measure of an arc is equal to the measure of its corresponding central angle.

Front

What is the relationship between a tangent line and a radius at the point of tangency?

Back

A tangent line is perpendicular to the radius at the point of tangency.

Front

What is the formula for the circumference of a circle?

Back

Circumference = 2πr, where r is the radius.

Front

How do you calculate the length of an arc?

Back

Arc length = (central angle/360) × Circumference.

Front

What is the measure of a semicircle?

Back

180 degrees.

Front

What is the inscribed angle theorem?

Back

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

Front

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

Back

The measure of the angle formed is equal to half the sum of the measures of the arcs intercepted by the angle and its vertical angle.

Front

What is a diameter in a circle?

Back

A diameter is a chord that passes through the center of the circle and divides it into two equal halves.