Show that the following system of linear equations has no solution:
x+2y≤3,3x+4y≥12,x≥0,y≥1.
Converting the given inequation,we obtain,x+2y=3,3x+4y=12,x=0,y=1
Region represented by x+2y≤3
The line x+2y=3 meets the coordinate axes at (0,32) and (3,0).We find that satisfies containing origin represents the solution set of the inequation x+2y≤3.
Region represented by 3x+4y≥12
The line 3x+4y=12 meets the coordinate axes at (0,3) and (4,0).We find that satisfies containing (0,0) does not satisfy inequation 3x+4y≥12.
Region represented by x≥0
Clearly,x≥0 represents the region lying on the right side of y-axis.
Region represented by y≥1
The line y=1 is parallel to x-axis (0,0) does not satisfy inequation y≥1.So the region lying above the line y=1 is represented by y≥1.
From graph we can see that there is no common region bounded by all the four inequalities.So there is no solution set satisfying the given inequalities.