General non-linear polynomial system solving defied mathematicians for many years. Approximate methods were the only alternative until the sixties, when the first general and effective method was found (Gröbner bases method). Although implementations of Gröbner bases' algorithm are incorporated to all Computer Algebra Systems, they are only known to a small number of members of the scientific community, most of them mathematicians. Although non-linear polynomial system solving is many times a huge task, there are situations where an exact solution is needed. We present an elementary introduction to the geometric interpretation of DERIVE's SOLVE command for polynomial equations and systems.