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Maximize Z=8x+9y, subject to the contra...

Maximize `Z=8x+9y`, subject to the contraints given below:
`2x+3y le 6, 3x-2y le 6, y le 1, x,y ge 0`

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To maximize the function \( Z = 8x + 9y \) subject to the given constraints, we will follow these steps: ### Step 1: Identify the Constraints The constraints given are: 1. \( 2x + 3y \leq 6 \) 2. \( 3x - 2y \leq 6 \) 3. \( y \leq 1 \) 4. \( x \geq 0 \) 5. \( y \geq 0 \) ### Step 2: Convert Inequalities to Equations To graph the constraints, we convert the inequalities into equations: 1. \( 2x + 3y = 6 \) 2. \( 3x - 2y = 6 \) 3. \( y = 1 \) 4. \( x = 0 \) (y-axis) 5. \( y = 0 \) (x-axis) ### Step 3: Graph the Constraints We will plot the lines corresponding to the equations on a graph and identify the feasible region. 1. For \( 2x + 3y = 6 \): - When \( x = 0 \), \( y = 2 \) (point (0, 2)) - When \( y = 0 \), \( x = 3 \) (point (3, 0)) 2. For \( 3x - 2y = 6 \): - When \( x = 0 \), \( y = -3 \) (not in the feasible region) - When \( y = 0 \), \( x = 2 \) (point (2, 0)) - When \( x = 2 \), \( y = 0 \) gives us the point (2, 0). 3. For \( y = 1 \): - This is a horizontal line at \( y = 1 \). ### Step 4: Identify the Feasible Region The feasible region is bounded by the lines we plotted and is the area where all constraints are satisfied. The vertices of this region can be found by solving the equations of the lines. ### Step 5: Find the Intersection Points 1. **Intersection of \( 2x + 3y = 6 \) and \( y = 1 \)**: \[ 2x + 3(1) = 6 \implies 2x + 3 = 6 \implies 2x = 3 \implies x = \frac{3}{2} \] Point B: \( \left(\frac{3}{2}, 1\right) \) 2. **Intersection of \( 2x + 3y = 6 \) and \( 3x - 2y = 6 \)**: Multiply the first equation by 2: \[ 4x + 6y = 12 \] Multiply the second equation by 3: \[ 9x - 6y = 18 \] Adding these: \[ 13x = 30 \implies x = \frac{30}{13} \] Substitute \( x \) back to find \( y \): \[ 2\left(\frac{30}{13}\right) + 3y = 6 \implies 3y = 6 - \frac{60}{13} = \frac{78 - 60}{13} = \frac{18}{13} \implies y = \frac{6}{13} \] Point C: \( \left(\frac{30}{13}, \frac{6}{13}\right) \) 3. **Intersection of \( 3x - 2y = 6 \) and \( y = 0 \)**: \[ 3x = 6 \implies x = 2 \] Point D: \( (2, 0) \) 4. **Intersection of \( y = 0 \) and \( x = 0 \)**: Point E: \( (0, 0) \) ### Step 6: Evaluate Z at Each Vertex Now we evaluate \( Z = 8x + 9y \) at each vertex: 1. At \( (0, 1) \): \[ Z = 8(0) + 9(1) = 9 \] 2. At \( \left(\frac{3}{2}, 1\right) \): \[ Z = 8\left(\frac{3}{2}\right) + 9(1) = 12 + 9 = 21 \] 3. At \( \left(\frac{30}{13}, \frac{6}{13}\right) \): \[ Z = 8\left(\frac{30}{13}\right) + 9\left(\frac{6}{13}\right) = \frac{240}{13} + \frac{54}{13} = \frac{294}{13} \approx 22.615 \] 4. At \( (2, 0) \): \[ Z = 8(2) + 9(0) = 16 \] 5. At \( (0, 0) \): \[ Z = 8(0) + 9(0) = 0 \] ### Step 7: Determine Maximum Value The maximum value of \( Z \) occurs at the point \( \left(\frac{3}{2}, 1\right) \) with \( Z = 21 \). ### Final Answer The maximum value of \( Z \) is \( 21 \) at the point \( \left(\frac{3}{2}, 1\right) \). ---
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