Suppose That the Optimal Values of the Decision Variables to a Two-Variable

Multiple Choice

Suppose that the optimal values of the decision variables to a two-variable linear programming problem remain the same as long as the slope of the objective function lies between the slopes of the following two constraints: 2X1 + 3X2 < 26
2X1 + 2X2 < 20
The current objective function is:
8X1 + 9X2 = Z
Which of the following statements about the range of optimality on c1 is TRUE?

A) 0 < c1 < 2
B) 2 < c1 < 6
C) 6 < c1 < 9
D) 9 < c1 < 12