Basic Geometry Terms

Front

What is a line?

Back

A line is one-dimensional and extends without end in two directions.

Front

What are collinear points?

Back

Collinear points are points that lie on the same line.

Front

What are vertical angles?

Back

Vertical angles are two angles whose sides form two pairs of opposite rays.

Front

What is a linear pair?

Back

A linear pair consists of two adjacent angles whose noncommon sides are opposite rays.

Front

What is a plane?

Back

A plane is two-dimensional and extends without end, even though the drawing appears to have edges.

Front

What is a line segment?

Back

A line segment is a part of a line that has two endpoints.

Front

What is a ray?

Back

A ray is a part of a line that has one endpoint and extends infinitely in one direction.

Front

What are adjacent angles?

Back

Adjacent angles are two angles that share a common side and a common vertex.

Front

What are supplementary angles?

Back

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

Front

What is a right angle?

Back

A right angle is an angle that measures exactly 90 degrees.