12 terms

Point

An exact location in space

Line

A straight path of points that goes on and on in two directions

Line Segment

A part of a line-it has two endpoints

Ray

A part of a line-it has one endpoint and continues on and on in only one direction

Angle

Formed by two rays that have the same endpoint

Vertex

The point where two rays meet OR where the sides of a polygon meet OR the point where three or more edges of a solid figure meet

Right Angle

An angle that forms a square corner at 90 degrees

Acute Angle

An angle that is less than a right angle (less than 90 degrees)

Obtuse Angle

An angle that is greater than a right angle (greater than 90 degrees)

Parallel Lines

In a plane, lines that never intersect

Intersecting Lines

lines that pass through the same point

Perpendicular Lines

Two lines that intersect to form right angles