e graphical methods to solve the following linear programming problem: Minimize \( z = 4x + 7y \) Subject to: 1. \( x - y \geq 1 \) 2. \( 3x + 2y \geq 18 \) 3. \( x \geq 0, y \geq 0 \) What is the optimal solution for this linear programming problem? A) \( x = 3, y = 2, z = 26 \) B) \( x = 4, y = 1, z = 31 \) C) \( x = 2, y = 3, z = 29 \) D) \( x = 1, y = 4, z = 33 \)