Front

What is the definition of a circle?

Back

A circle is a set of points in a plane that are equidistant from a fixed point called the center.

Front

What is a radius of a circle?

Back

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

Front

What is a tangent to a circle?

Back

A tangent is a line that touches the circle at exactly one point.

Front

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

Back

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

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 formula for the area of a circle?

Back

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

Front

What does it mean for a line to be secant to a circle?

Back

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

Front

What is the difference between a secant and a tangent?

Back

A secant intersects the circle at two points, while a tangent touches the circle at exactly one point.

Front

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

Back

If a triangle formed by the line and two points on the circle is a right triangle, then the line is tangent to the circle.

Front

What is the significance of points of tangency?

Back

Points of tangency are the points where a tangent line touches the circle.