Solving a non-linear system with matlab

Hi,

I`m having a non-linear system of equations, with 16 equations and 16 variables. I`m not sure if I should insert some of the equations, so that I got less equations with less variables. I use the lsqnonlin-solver at the moment and when I´m inserting some of the equations I get different results. So i don`t know, if it is correct to insert equations or if it is better to keep my 16 equations.

If I use all 16 equations and I use the boundaries for lsqnonlin one of my variables hits the upper boundary all the time and I tried to eliminate that by inserting the equation for this variable in the other equations but the results changed dramaticaly.

Thanks for your help.

Greetings