Answer:
To solve the linear programming problem, we need to first graph the feasible region determined by the constraints, and then evaluate the objective function at each corner point of the feasible region to find the maximum value of z.
Plotting the lines corresponding to the inequalities, we get:
Graph of the feasible region:
The feasible region is the shaded polygon in the graph. We can see that the vertices of the feasible region are (2, 9), (2, 12), (4, 7), and (8, 2).
Next, we evaluate the objective function at each of these vertices to find the maximum value of z.
At (2, 9): z = 7x + 2y = 7(2) + 2(9) = 23
At (2, 12): z = 7x + 2y = 7(2) + 2(12) = 31
At (4, 7): z = 7x + 2y = 7(4) + 2(7) = 35
At (8, 2): z = 7x + 2y = 7(8) + 2(2) = 58
Therefore, the maximum value of z is 58, which occurs at the point (8, 2).
Hence, the answer is: the maximum value of z is 58.