4-13 Naming Angles & Rays

A plane is a flat surface that goes on and on in all directions.  A plane has no thickness.  Circles and squares are plane figures because they are part of a plane.  Plane figures have definite boundaries that give them their shape, while a plane goes on forever in all directions.  A plane does not have boundaries.  Look at plane M below.

A line goes on forever in two directions.  A ray has one end point and continues in only one direction.  A ray is a part of a line.  You name a ray beginning with the end point.  Look at the ray ST below.

An angle is formed by two rays that have the same end points.  The end point the two rays share is called the vertex.  Look at angle RST below.

When you name an angle you put the vertex in the middle.

S is the vertex of angle RST.

Name the planes, rays, and angles below.

Ray	Angle E
Plane	Ray
Ray	Plane
Angle N	Ray
Angle T	Angle B
Name the angles above Angle SY Angle YP Angle PQ Angle QY	Name the angles above Angle KB Angle FJ Angle CB Angle KC