Term
Ruler Postulate (Chapter 1) 

Definition
The points on a line can be matched one to one with the real numbers. The real number that corresponds to a point is the coordinate of the point. The distance between points A and point B, written as AB is the absolute value of the difference between the coordinates of A and B. (page 9) 


Term
Segment Addition Postulate (Chapter 1) 

Definition
If B is between A and C,then AB +BC = AC. If AB +BC = AC, then point B is between A and C. (Page 10) 


Term
Protractor Postulate (Chapter 1) 

Definition
Consider ray OB and point A on one side of ray OB. The rays of the form ray OA can be matched one to one with the real numbers from 0 to 180. The measure of angle AOB is equal to the absolute value of the difference between the real numbers for ray OA and ray OB. (Page 24) 


Term

Definition
A point is an undefined term which has no dimension, is usually represented by a dot, and named with a CAPITAL LETTER!
(Page 2) 


Term

Definition
A line is another one of those undefined terms. It has no dimension and is represented by a straight segment with arrowheads representing that it does in fact stretch into infinity. Lines can be named with TWO POINTS which lie on the line OR a LOWERCASE SCRIPT (OR CURSIVE) LETTER.(Page 2). 


Term

Definition
A plane is another undefined term. It has two dimensions. It is represented by a shape that looks like a floor or a wall(usually a trapezoid or a rectangle). It also extends without end.
IMPORTANT: Through any three noncollinear points, you can create a plane. Through three collinear points, you can create an infinite amount of planes.
Planes can be named by THREE NONCOLLINEAR POINTS or by a LETTER, usually in a bold font. (Page 2) 


Term

Definition
Collinear points are points that lie on the same line. (Page 2) 


Term

Definition
Coplanar points are points that lie on the same plane. (Page 2). 


Term

Definition
Line segments are lines which have termination points. They are named by THE ENDPOINTS. They can be in either order, as long as they have either the word line segment, segment, or a line WITHOUT arrow heads above the two letters.
For example:
Line segment AB consists of the endpoints of A and B and all the points on line AB which are between points A and B. (Page 3) 


Term

Definition
Opposite rays lie on the same line and have the same starting point. They go in opposite directions.
If you want to see an example of opposite rays, please review page 3. 


Term

Definition
A postulate is a rule which is accepted, and needs no proof.
Lists of postulates are on page 926. 


Term

Definition
Another word for "postulate".
A rule that is accepted without proof
List of axioms/postulates on page 926. 


Term

Definition
A rule that can be proved. It is also a true statement that follows as a result of other true statements.
For a list of Theorems, please see page 927. 

