To maximize a linear objective function:
1. Identify all vertices of the feasible region.
2. Substitute the coordinates of each vertex into the objective function.
3. Choose the highest value for maximization.
Step 1: The objective function \( z = 5x + 2y \) is maximized at one of the vertices of the feasible region \( R_1 \). The vertices of \( R_1 \) are \( A(0, 50) \), \( B(20, 40) \), and \( C(50, 100) \).
Step 2: Evaluate \( z \) at each vertex: - At \( A(0, 50) \): \[ z = 5(0) + 2(50) = 100. \] - At \( B(20, 40) \): \[ z = 5(20) + 2(40) = 100 + 80 = 180. \] - At \( C(50, 100) \): \[ z = 5(50) + 2(100) = 250 + 200 = 450. \]
Step 3: Conclusion: The maximum value of \( z = 5x + 2y \) is 450 at \( C(50, 100) \).