Hi, I found a program called SIMPLEXA for the 86 but I don't know how to use it. I only know the input is a matrix, but have no idea about row's and column's content. I tried every combination I could imaginate. For exemple, how to solve this: Max x+2y+3z x+y<=10 2x+z<=8 y-z<=5 (Note: this is just an exemple, I'm not sure there is an optimum). Thanks a lot! Sandor