Converting from primal to dual linear problem

Question

If a primal problem has an unrestricted variable then the corresponding dual constraint is an equality.

This is what I've been told.

However, the following online primal to dual conversion software states the same fact but doesn't use it in the solution.

Could someone clarify this for me:

Should it not be: $y_1 = 6$ ?

Answer 1

Yes, it should. I think you typed incorrect data. This is what I got. Note the difference in the primal problem representation. In your case it says $$ x_1,x_2\ge 0,\ X_1\text{ unrestricted} $$ but $X_1$ (capital) is not a variable there.