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The optimal value of the objective function of the LPP, Minimize Z=3x−2yZ = 3x - 2y subject to constraints x+y≥10x + y \ge 10, 3x+5y≥153x + 5y \ge 15, x≥0x \ge 0, y≥0y \ge 0, is equal to:

Solution

✅ Drop

To find the feasible region, we look at the boundaries:

Constraint 1: x+y≥10x + y \ge 10. The line x+y=10x + y = 10 passes through (10,0)(10, 0) and (0,10)(0, 10). Since it is ≥\ge, the region is above this line.

Constraint 2: 3x+5y≥153x + 5y \ge 15. The line 3x+5y=153x + 5y = 15 passes through (5,0)(5, 0) and (0,3)(0, 3).

Solution figure for CUET Mathematics 2025 13 May Shift 2 question 29 (Algebra)

Non-negativity: x≥0,y≥0x \ge 0, y \ge 0 restricts us to the first quadrant.

Observation: Notice that the line x+y=10x + y = 10 is further from the origin than 3x+5y=153x + 5y = 15 in the first quadrant. Therefore, x+y≥10x + y \ge 10 is the "stricter" constraint, making 3x+5y≥153x + 5y \ge 15 redundant.

We also see that there is no bounded region in this question.


Since we are minimizing and the feasible region is unbounded in the positive yy direction:

As yy increases (e.g., at point (0,100)(0, 100)), ZZ becomes 3(0)−2(100)=−2003(0) - 2(100) = -200.

As y→∞y \to \infty, Z→−∞Z \to -\infty.


The objective function is unbounded. In standard LPP theory, this means there is no finite optimal (minimum) value.

Hence, NTA dropped this question! No marks were awarded.

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