Indeed, there are plenty of open source solutions that can solve your particular problem, and many problems don't need any sort of symbolic tools. There's also

Indeed, there are plenty of open source solutions that can solve your particular problem, and many problems don't need any sort of symbolic tools. There's also Octave with a nice collection of packages on Octave-Forge, there's PARI (included in Sage), and there's LAPACK, and I'm sure there are others I'm either forgetting or haven't heard of.