Unit 9A: Circles Review 2024-2025

Front

What is a circle?

Back

A circle is a shape consisting of all points in a plane that are at a given distance from a fixed point, called the center.

Front

What is the diameter of a circle?

Back

The diameter is a segment that passes through the center of the circle and connects two points on the circle. It is twice the length of the radius.

Front

What is a radius?

Back

The radius is a segment that connects the center of the circle to any point on the circle.

Front

What is a chord?

Back

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

Front

What is a tangent?

Back

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

Front

What is the relationship between the radius and diameter?

Back

The diameter is twice the length of the radius.

Front

How do you find the circumference of a circle?

Back

The circumference can be found using the formula C = πd, where d is the diameter.

Front

What is the area of a circle?

Back

The area can be calculated using the formula A = πr², where r is the radius.

Front

What is the central angle of a circle?

Back

A central angle is an angle whose vertex is at the center of the circle and whose sides are radii.

Front

What is an inscribed angle?

Back

An inscribed angle is an angle formed by two chords in a circle which have a common endpoint.