# NCERT Chapter Summary: Coordinate Geometry

To locate the **position** of an object or a point in a plane, we require two perpendicular lines. One of them is horizontal, and the other is vertical. The plane is called the **Cartesian**, or coordinate plane and the lines are called the **coordinate axes**.

The horizontal line is called the **x - axis**, and the vertical line is called the **y - axis**. The coordinate axes divide the plane into four parts called **quadrants**. The point of intersection of the axes is called the **origin**.

The distance of a point from the y - axis is called its x-coordinate, or **abscissa**, and the distance of the point from the x-axis is called its y-coordinate, or **ordinate**. If the abscissa of a point is x and the ordinate is y, then (x, y) are called the coordinates of the point.

The coordinates of a point on the x-axis are of the form (x, 0) and that of the point on the y-axis are (0, y). The coordinates of the origin are (0, 0).

The coordinates of a point are of the form (+ , +) in the first quadrant, (–, +) in the second quadrant, (–, –) in the third quadrant and (+, –) in the fourth quadrant, where + denotes a positive real number and – denotes a negative real number.

If x ≠ y, then (x, y) ≠ (y, x), and (x, y) = (y, x), if x = y.

### Class 10

To locate the position of a point on a plane, you require a pair of **coordinate axes**. The distance of a point from the y-axis is called its x-coordinate, or abscissa. The distance of a point from the x-axis is called its y-coordinate, or ordinate.

The coordinates of a point on the x-axis are of the form (x, 0), and of a point on the y-axis are of the form (0, y).