Cartesian Plane

It is known as the Cartesian plane, to two perpendicular number lines, one horizontal and one vertical, which intersect at a point called the origin or point 0.

The purpose of the Cartesian plane is to describe the position or location of a point in the plane, which is represented by the coordinate system.

Parts of the Cartesian plane

The elements and characteristics that make up the Cartesian plane are the coordinate axes, the origin, the quadrants, and the coordinates.

Coordinate axes

Coordinate axes are called the two perpendicular lines that interconnect at a point in the plane. These lines are called the abscissa and the ordinate.

• Abscissa: the abscissa axis is arranged horizontally and is identified by the letter "x"
• Ordinate: the ordinate axis is oriented vertically and is represented by the letter "y".

Origin or point 0

The origin is called the point at which the “x” and “y” axes intersect, the point to which the value of zero (0) is assigned.

Quadrants of the Cartesian plane

Quadrants are the four areas that are formed by the union of the two perpendicular lines. The points of the plane are described within these quadrants.

Quadrants are traditionally numbered with Roman numerals: I, II, III, and IV.

• Quadrant I: the abscissa and the ordinate are positive.
• Quadrant II: the abscissa is negative and the ordinate is positive.
• Quadrant III: the abscissa and the ordinate are negative.
• Quadrant IV: the abscissa is positive and the ordinate negative

 Coordinates of the cartesian plane

The coordinates are the numbers that give us the location of the point on the plane. The coordinates are formed by assigning a certain value to the "x" axis and another value to the "y" axis. 

P (x, y), where:

• P = point in the plane;
• x = axis of the abscissa (horizontal).
• y = axis of the ordinate (vertical).

For example

• quadrant I, P (6, 5);
• quadrant II, P (-5, 3);
• quadrant III, P (4.5, -3.5)