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# Ordinate

The ordinate of an ordered pair (x, y) is its second component, i.e. it is y. The ordered pair (x, y) is used to denote a point in Cartesian Coordinate system. It is the second of the two terms by which a point is referred to, in a system of fixed Cartesian Coordinate axes. The first coordinate, i.e., "x" coordinate, is called the abscissa. Cartesian co-ordinate system specifies each point uniquely in a plane by a pair of numerical co-ordinates, which are the distances from the point to two fixed axes, measured in the same unit of length.

For example, we can say that for a point A, having coordinate (7, 8), has an ordinate 8. and a point P, having coordinate (8, -10), has an ordinate -10. In the first example, the ordinate is positive, we need to go 8 equal divisions from origin towards the positive direction of Y-axis, and for the second example, we have to go 10 divisions towards the negative direction of Y-axis, since it is -10.

## Graph Ordinate

This Graph is an illustration of a Cartesian coordinate system, having 4 distinct points marked. The 4 points are (2, 3) in green, (-3, 1) in red, (-1.5, -2.5) in blue, and (0, 0) the origin in purple. In the point (2, 3), While graphing the ordinate three divisions are covered in the positive direction of the Y- axis.

Likewise for the point (-1.5, -2.5), two and half divisions are marked from the origin (0, 0) towards the negative direction of the Y- axis, since the ordinate is negative.

## Relation of Co-ordinate System with the Y-axis

The ordinate solely and entirely depends on the Y-axis. So While marking it, one needs to go along or parallel to the positive or negative direction of the Y axis.

## Abscissa and Ordinate

The distance of a point from y-axis measured along the x-axis is called abscissa or x coordinate of the point and the distance of a point from x-axis measured along the y-axis is called ordinate. The abscissa and ordinate taken together are called coordinate and these coordinates are always written in the open bracket, the abscissa being written first and then ordinate separated by a comma. If x and y are abscissa and ordinate respectively, then the position of the point A in the plane (shown in figure) is denoted by the ordered pair (x, y).

From the figure: AB is the ordinate (y-coordinate of the point A) while OB is the abscissa (x-coordinate of point A).
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