Flashcard Review Arcs, Sectors, & Tangents

Front

What is a tangent in relation to a circle?

Back

A tangent is a straight line that touches a circle at exactly one point, known as the point of tangency.

Front

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

Back

The tangent is perpendicular to the radius drawn to the point of tangency.

Front

How do you calculate the perimeter of a shape involving tangents and arcs?

Back

To find the perimeter, sum the lengths of all the tangent segments and the lengths of the arcs.

Front

What is an arc in a circle?

Back

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

Front

How do you find the measure of an arc?

Back

The measure of an arc can be found using the central angle that subtends the arc.

Front

What is the formula for the area of a sector?

Back

Area of a sector = (θ/360) × πr², where θ is the central angle in degrees and r is the radius.

Front

What is the formula for the area of a circle?

Back

Area = πr², where r is the radius of the circle.

Front

How do you find the length of an arc?

Back

Length of an arc = (θ/360) × 2πr, where θ is the central angle in degrees and r is the radius.

Front

What is the measure of an angle formed by two tangents drawn from a point outside a circle?

Back

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

Front

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

Back

The measure of the angle formed by two intersecting chords is equal to the average of the measures of the arcs intercepted by the angle and its vertical angle.