Big m method / two-phase method

[csc2iffy]

Homework Statement

Minimize Z = 3.5x + 6.5y
subject to
1. (1/3)x + y ≥ 1
2. 3.8x + 2.4y ≥ 5
and x ≥ 0, y ≥ 0

Use Big M method and then Two-Phase method interactively with IOR.jar and compare answers.

Homework Equations

The Attempt at a Solution

I am getting really confused with IOR, but this is what I have

Big M Method:

Minimize Z = 3.5x + 6.5y + Ma + Mb --> Max(-Z) = -3.5x - 6.5y - Ma - Mb -->
-Z + 3.5x + 6.5y + Ma + Mb = 0
subject to
1. (1/3)x + y - u + a = 1
2. 3.8x + 2.4y - v + b = 5
and x, y, u, v, a, b ≥ 0

I attached my IOR txt file... just wondering if it's all right?
Not sure how to do the Two-Phase method on iOR, there isn't an example in the book.. help please?

 

[Ray Vickson]

The two-phase method starts by trying to get a basic feasible solution (or prove infeasibility). It does this by first solving the problem min (a + b), subject to the constraints you wrote for the Big M problem.

RGV