Hi all Dear Georgios Thank you a lot, I am not expert in Maple, I began using it just these days. I will study your solution. Any way my propuse is just to give Maple a set of inequalities and check if there is a solution, all the variables are positive. I dont interested what is the solution. The inequalities will generated by a system which I had build and, such inequalities will be the input on the Maple program. Inequalities : x=y and x=2y have no solution (x and y are possitive), therefore Maple sould return No solution (I dont under stand why use the range -10..10, any solution will be ok ) I will be very thankfull if you provide me with sites or books which help i a simple way how sould I create the coorect syntax of the Inequalities!! and can directly exprot my inequalities to Maple ?? I will appreciate any help