Special Segments in Circles

Front

What is a tangent line to a circle?

Back

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

Front

What is the relationship between the radius and a tangent line?

Back

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

Front

Define a secant line in relation to a circle.

Back

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

Front

What is the formula for the area of a circle?

Back

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

Front

What is the formula for the circumference of a circle?

Back

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

Front

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

Back

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

Front

What is the power of a point theorem?

Back

The power of a point theorem states that for a point outside a circle, the square of the length of the tangent segment from the point to the circle is equal to the product of the lengths of the segments of any secant line drawn from that point.

Front

If two chords intersect inside a circle, what is the relationship between the segments?

Back

The products of the lengths of the segments of each chord are equal.

Front

What is the inscribed angle theorem?

Back

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

Front

How do you find the length of an arc?

Back

Arc length = (θ/360) × 2πr, where θ is the central angle in degrees and r is the radius.