Let x1 and x2 be 0-1 variables whose values indicate whether projects 1 and 2 are/are not done.Which of the following answers indicates that project 2 can be done only if project 1 is done? A)x₁ + x₂ = 1 B)x₁ + x₂ = 2 C)x₁ − x₂ ≤ 0 D)x₁ − x₂ ≥ 0

Question

Quizplus · Accepted Answer

The constraint x1 - x2 ≥ 0 ensures that if project 2 is done (x2 = 1), project 1 must also be done (x1 = 1), since otherwise the left hand side of the constraint would be negative. Therefore, D is the correct choice.

Let X1 and X2 Be 0-1 Variables Whose Values Indicate