# Plotting Points on a Coordinate Plane (Coordinates on a Graph)

The Cartesian Coordinate System is two perpendicular and graduated lines that intersect at a point called the origin of the coordinate axis.

In the plane attributed to this system of coordinates, we can mark any point with a pair of coordinates(-coordinate and -coordinate). Before we get to know and , let's first get to know the graphic of the Coordinate Axis.  Perpendicular lines make up four quadrants, as shown below.  The two graduated axes have their own name:

• The horizontal axis is called the -axis or the abscissa axis, and is graded incremental from left to right.
• The vertical axis is called the -axis or the ordinates axis, and it is graded incremental from bottom to top.

The point of their intersection is called the origin of The Cartesian Coordinate System, and we write

## How to plotting a given point on a coordinate plane.

• We mark the real number on the -axis and drawing a line (1) pass through and parallel to the -axis.
• We mark the real number on the -axis and drawing a line (2) pass through and parallel to the -axis.
• The intersection of the two lines (1) and (2) is the coordinates of the point  Example1:

Let's plot the point on the coordinates axis.

We mark the number 2 in the -axis, and we mark the number -3 in the -axis.  Let's plot the point on the coordinates axis.

We mark the number 0 in the -axis, and we mark the number 6 in the -axis.

### Note:

When an abscissa is zero , the point belongs to the ordinate axis.  Let's plot the point on the coordinates axis.

We mark the number -3 in the -axis, and we mark the number 0 in the -axis.

### Note:

When an ordinate is zero , the point belongs to the abscissa axis.  Let's plot the point on the coordinates axis.

We mark the number 1 in the -axis, and we mark the number 5 in the -axis.  Let's plot the point on the coordinates axis.

We mark the number -6 in the -axis, and we mark the number -4 in the -axis.  