Simple linear programming example from

Vanderbei, R.J. (2000).  
Linear programming, Foundations and extensions.
Kluwer Academic Publishers, Boston.

Example 2.7 - unbounded 

####################################################################

## DECISION VARIABLES

x1
x2

## END DECISION VARIABLES

## INEQUALITIES

-x1 -x2    < -3
-x1 + x2   <-1
-x1 + 2*x2 < 2

## END INEQUALITIES

## MAXIMISATION

x1 + 3*x2
## END MAXIMISATION
