Co - Ordinate Geometry

Co - Ordinate Geometry

1. The branch of geometry which involves applications of algebra is known as "co ordinate geometry".

   • The system that is used here is "Cartesian system".
     • Great French Mathematician Rene Descartes invented this system, which is also known as "Rectangular System".

2. Through this system: to locate the position of a point in the Cartesian plane, we require two perpendicular axes. The horizontal one is known as x - axis (abscissa), and the vertical on is known as y - axis (ordinate).

3. The point of intersection of the axes is called Origin (0,0).

4. The coordinate axes divide the plane into four parts called quadrants: first quadrant (+,+), second quadrant (-,+), third quadrant (-,-), and fourth quadrant (+,-).

5. The distance of a point from the y axis is called its X coordinate, and the distance of a point from the x axis is called its Y coordinate.

6. If the abscissa of a point is x and the ordinate is y, then (x, y) are called the coordinates of that point.

7. 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 of the form (0, y).

8. If x is not equal to y, then (x, y) is not equal to (y, x); and vice versa.