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Question
Solve the following LPP:
Maximize z = 2x + 3y subject to x - y ≥ 3, x ≥ 0, y ≥ 0.
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Solution
First we draw the lines AB whose equations are x - y = 3.
| Line | Equation | Points on the X-axis | Points on the Y-axis | Sign | Region |
| AB | x - y = 3 | A(3, 0) | B(0, -3) | ≥ | non-origin side of line AB |

The feasible region is shaded which is unbounded. Therefore, the value of objective function can be increased indefinitely. Hence, this LPP has unbounded solution.
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