The ordered pair of real number is called a dimensional system or Cartesian plane or coordinate system. If (x, y) are the dimension of the point P, then the first number (component) of the ordered pair is called the x – dimension or Abscissa of P and the second number of the ordered pair the Y – dimension or Ordinate of P.

NOTE:

Abscissa is always the first element of an ordered pair.

This is x-axis

And

Ordinate is always the second element of an ordered pair

This is y-axis

Four quadrant

dimensional system divide into four quadrants

Quadrant 1 : All point (x, y) with x>0, y>0

Quadrant 2 : All point (x, y) with x< 0, y>0

A dimensional system is a framework used to represent and measure physical quantities in various dimensions. It provides a structured approach to understanding and organizing these quantities. One specific example is Quadrant 3, which represents all points (x, y) where x is less than 0 and y is less than 0 in a Cartesian coordinate system.

Quadrant 4 : All point (x, y) with x>0, y<0

The point P in the dimension (x, y) is called the graph of (x, y).

Thus given a set of ordered pairs of real numbers, the graph of the is

aggregate of all point in the plane that correspond to ordered pairs

of the set.

P point in the plane:

P is any point on the plane. P can be located by using the ordered pair of real numbers.

Through P draw lines parallel to coordinate axis meeting x-axis on R and y-axis at S

Let the directed distance line OR=x, and the directed distance line OS= y

Dimension (x, y)

The ordered pair (x, y) gives us enough information to locate the point P.

Thus, with every point P in the plane, we can associate an ordered pair of real number

(x, y) and we can say that P has dimension (x, y). It may be noted that x and y are the directed

distance of P from the Y-axis and the X-axis, respectively. The reverse of this technique also

provide a method for association of exactly one point in the plane of any ordered pair (x, y)