ABSTRACT
In 2-D space or the XY plane, the distance between the points is
( ) ( )x x y y1 2 1 22 2− + − . (4.3)
In 3-D space, the distance between the points is
( ) ( ) ( )x x y y z z1 2 1 2 1 22 2 2− + − + − . (4.4)
With respect to origin, the 2-D space or XY plane is divided into four regions, as shown in Figure 4.1: first quadrant, second quadrant, third quadrant, and fourth quadrant. It is clear from the figure that when the sign of the abscissa or ordinates alters, the point lies in different quad-
TABLE 4.1
Defining Method in Coordinate Systems
Example 4.3
Find the equation of a line that connects two points (5,2) and (9,25).
