Graphical Solution of Linear Inequalities in 2 variables
A line divides the Cartesian plane into two equal parts . A point in Cartesian plane will either lie on a line or will lie in either of half planes . The region containing all the solutions of an inequality is called the solution region .
In order to identify the half plane represented by an inequality , it is just sufficient to take any point ( a , b ) ( not online ) and check whether it satisfies the inequality or not . If it satisfies , then the inequality represents the half plane and shade the region which contains the point , otherwise , the inequality represents that half plane which does not contain the point within it . For convenience , the point ( 0 , 0 ) is preferred .
Example : x + 2y > 9