Write the abscissa and ordinate of the $(5,0)$.

1. Cartesian Plane:

(i) In order to locate the position of a point in a plane, we require two perpendicular lines. One of them is horizontal and another is vertical. The plane is called the Cartesian plane and the lines are known as the coordinate axes. The horizontal line is called the $X-$axis and the vertical line is known as the $Y-$axis.

(ii) The coordinate axes divide the plane into four parts which are known as quadrants.

(iii) The point of intersection of the coordinate axes is called the origin.

(iv) The distance of a point from $Y-$axis is called it's $x-$coordinate, or abscissa and the distance of the point from $X-$axis is called it's $y-$coordinate or ordinate.

2. Position of a Point:

(i) If $x$ and $y$ denote respectively the abscissa and ordinate of a point $P,$ then $(x,y)$ are called the coordinates of the point $P.$

(ii) The $y-$coordinate of every point on $x-$axis is zero. So, the coordinates of any point on $x-$axis are of the form $(x,0).$

(iii) The $x-$coordinate of every point on $y-$axis is zero. So, the coordinates of any point on $y-$axis are of the form $(0,y).$

(iv) The coordinates of the origin are $(0,0).$

3. Sign Convention of Points in Quadrants:

The signs of coordinates $(x,y)$ of a point in various quadrants are as given below: