Show that the solution set of the following linear constraints is empty:

x - 2y 0, 2x - y - 2, x 0 and y 0


Consider the inequation x - 2y 0:


x 2y


y


consider the equation y = . This equation’s graph is a straight line passing through origin.


Now consider the inequality y


Here we need the y value less than or equal to


the required region is below origin.


Therefore the graph of the inequation y is fig.10a



Fig 10a


Consider the inequation 2x - y - 2 :


y 2x + 2


Consider the equation y = 2x + 2


Finding points on the coordinate axes:


If x = 0, the y value is 2 i.e, y = 2


the point on Y axis is A(0,2)


If y = 0, 0 = 2x + 2


x = - 1


The point on X axis is B( - 1,0)


Now consider the inequality y 2x + 2


Here we need the y value greater than or equal to 2x + 2


the required region is above point A.


Therefore the graph of the inequation y 2x + 2 is fig. 10b



Fig 10b


y 0 is the region above X - axis


x 0 is the region right side of Y - axis


Combining the above results, we’ll get



As they is no common area of intersection , there is no solution for the given set of simultaneous inequations.


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