Flashcardizz L12.1 Circles Tangent Line Properties

Front

What is a tangent line?

Back

A tangent line 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 line and a radius at the point of tangency?

Back

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

Front

How do you determine if a line is tangent to a circle?

Back

A line is tangent to a circle if it intersects the circle at exactly one point.

Front

What is the length of a tangent segment from a point outside the circle to the point of tangency?

Back

The length of the tangent segment is equal to the square root of the difference between the square of the distance from the external point to the center of the circle and the square of the radius.

Front

If two tangent segments are drawn from a single external point to a circle, what can be said about their lengths?

Back

The two tangent segments are equal in length.

Front

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

Back

The angle formed is 90 degrees.

Front

How can you find the length of a tangent segment if you know the distance from the external point to the center and the radius?

Back

Use the formula: Length of tangent = √(distance from external point to center² - radius²).

Front

What is the significance of the point of tangency?

Back

The point of tangency is the only point where the tangent line touches the circle.

Front

In a circle, if a line is perpendicular to a radius at its endpoint on the circle, what can be concluded about the line?

Back

The line is a tangent to the circle.

Front

What is the formula for the length of a tangent segment from a point outside the circle?

Back

Length of tangent = √(d² - r²), where d is the distance from the external point to the center and r is the radius.