Circles, Angles and Segments

Front

What is a circle?

Back

A circle is a shape consisting of all points in a plane that are a fixed distance from a center point.

Front

What is the radius of a circle?

Back

The radius is the distance from the center of the circle to any point on its circumference.

Front

What is the diameter of a circle?

Back

The diameter is twice the length of the radius and is the longest distance across the circle.

Front

What is a chord in a circle?

Back

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

Front

What is the circumference of a circle?

Back

The circumference is the distance around the circle, calculated as C = 2πr, where r is the radius.

Front

What is an angle?

Back

An angle is formed by two rays with a common endpoint, called the vertex.

Front

What are complementary angles?

Back

Complementary angles are two angles whose measures add up to 90 degrees.

Front

What are supplementary angles?

Back

Supplementary angles are two angles whose measures add up to 180 degrees.

Front

What is a segment in a circle?

Back

A segment is a region of a circle bounded by a chord and the arc connecting the endpoints of the chord.

Front

What is the relationship between angles formed by intersecting lines?

Back

When two lines intersect, the opposite (or vertical) angles are equal.