Circles: Parts and Tangent Lines

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 a chord in a circle?

Back

A chord is a line segment whose endpoints lie on the circle.

Front

What is a diameter?

Back

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

Front

What is a radius?

Back

A radius is a line segment from the center of the circle to any point on the circle.

Front

What is a secant line?

Back

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

Front

What is the point of tangency?

Back

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

Front

How can you determine if a line segment is tangent to a circle?

Back

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

Front

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

Back

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

Front

What is the formula for the circumference of a circle?

Back

The circumference (C) of a circle is given by the formula C = 2πr, where r is the radius.

Front

What is the area of a circle?

Back

The area (A) of a circle is given by the formula A = πr², where r is the radius.