A linear programming problem is as follows:
Minimize $z = 2x + 3y$
Subject to the constraints $x ≥ 3,x ≤9, y ≥ 0, x-y≥ 0, x + y ≤ 14$. The feasible region has 5 corner points including
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (7, 7) and (3, 3)
Given LPP:
Minimize: $z = 2x + 3y$
Subject to constraints:
- $x \geq 3$
- $x \leq 9$
- $y \geq 0$
- $x - y \geq 0 \Rightarrow y \leq x$
- $x + y \leq 14$
To find corner points, graph all lines and find the intersection points within the feasible region.
Lines involved:
- $x = 3$
- $x = 9$
- $y = 0$
- $y = x$
- $x + y = 14$
Now calculate intersection points:
- Intersection of $x = 3$ and $y = 0$: (3, 0)
- Intersection of $x = 3$ and $x + y = 14$: $y = 11$ → (3, 11) → not feasible (since $y > x$)
- Intersection of $x = 3$ and $y = x$: $y = 3$ → (3, 3)
- Intersection of $x = 9$ and $y = 0$: (9, 0)
- Intersection of $x = 9$ and $x + y = 14$: $y = 5$ → (9, 5)
- Intersection of $y = x$ and $x + y = 14$:
Let $y = x$ → $x + x = 14 \Rightarrow x = 7$, $y = 7$ → (7, 7)
Now test feasibility for all points:
- (3, 0): ✔️
- (3, 3): ✔️
- (7, 7): ✔️
- (9, 0): ✔️
- (9, 5): ✔️
Therefore, the feasible region has 5 corner points:
${(3, 0), (3, 3), (7, 7), (9, 5), (9, 0)}$