Problem 1 Naming Points, Lines and Planes

1. What are two other ways to name Q T ↔ modified q t with left right arrow above  ?

   Two other ways to name Q T ↔ modified q t with left right arrow above  are T Q ↔ modified t q with left right arrow above  and line m.

   

   Think

   Why can figures have more than one name?

   Lines and planes are made up of many points. You can choose any two points on a line and any three or more noncollinear points in a plane for the name.

2. What are two other ways to name plane P?

   Two other ways to name plane P are plane RQV and plane RSV.

3. What are the names of three collinear points? What are the names of four coplanar points?

   Points R, Q, and S are collinear. Points R, Q, S, and V are coplanar.

✓ Got It?

1. 1. What are two other ways to name R S ↔ ? modified r s with left right arrow above , question mark
   2. What are two more ways to name plane P?
   3. What are the names of three other collinear points?
   4. What are two points that are not coplanar with points R, S, and V?

Take note Key Concept: Defined Terms

Definition	How to Name It	Diagram
A segment is part of a line that consists of two endpoints and all points between them.	You can name a segment by its two endpoints, such as A B ¯ eh b bar  (read “segment AB”) or B A ¯ . b eh bar , .
A ray is part of a line that consists of one endpoint and all the points of the line on one side of the endpoint.	You can name a ray by its endpoint and another point on the ray, such as A B → eh b vector  (read “ray AB”). The order of points indicates the ray's direction.
Opposite rays are two rays that share the same endpoint and form a line.	You can name opposite rays by their shared endpoint and any other point on each ray, such as C A → c eh vector  and C B → . c b vector , .