Bertini is a free software for solving polynomial systems numerically using homotoy continuation. It can be downloaded here: https://bertini.nd.edu/
Computing roots numerically
To run Bertini on a valid input file, run
bash-3.2$ bertini binding43.bertini
Bertini will then create files in the current directory containing the solutions. For large systems, it is recommended to run Bertini in parallel:
bash-3.2$ mpirun -np 16 bertini binding43.bertini
More information on how to run bertini can be found on its website.