CBSE Class 9th Coordinate Geometry- Cartesian System
Nov 29, 2017 11:38 IST
In this video we will learn about the Cartesian System of Geometry in which the coordinate plane is divided by the x and y axis.
A Cartesian system is the one which specifies a point plotted uniquely on a plane by a pair of numerical coordinates, having a pre-defined distance from the two fixed perpendicular coordinates, measured in the same unit of length.
The numbers are represented on a number line on which the points are marked at equal distances.
Two number lines are taken and intersected perpendicularly at the point zero also called the origin.
The numbers on the right side of the horizontal number line, also x- axis, are positive and that on the left side are negative.
The numbers to the top of the origin of the vertical number line, also y-axis, are positive and that below the origin are negative.
The x- axis and the y-axis divide the coordinate plane into four parts called the quadrant.
The quadrants are named in an anti-clockwise order, starting with I, II, III and IV.
In the first quadrant both the x and y coordinates are positive
In the second quadrant x coordinate is negative and the y coordinate is positive
In the third quadrant both x and y coordinates are negative, and
In fourth quadrant x coordinate is positive and the y coordinate is negative.
Any point can be depicted on the coordinate plane by specifying its perpendicular distances from the x and y coordinates.