Maximise `Z=-x+2y`
Subject to the constraints `xge3, x+yge5,x+2yge6,yge0`

Explanation

GIven the constraints are, x≥3,x+y≥5,x+2y≥6,y≥0 . Solving this
It can be seen that the feasible region is at corner points A(6,0),B(4,1) and C(3,2) where

value of `Z=−x+2y`

`A(6,0) Z=−6`

`B(4,1) Z=−2`

`C(3,2) Z=1`

As the feasible region is unbounded, therefore Z=1 may or may not be the maximum value

For this, we graph the inequality −x+2y>1 and check whether the resulting half plane has points in common with the feasible region or not
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