HP 50G "Bad Argument Value"

[BartDB]

You can also use the interactive numerical solver:

Red Shift NUM.SLV, then select 1. Solve equation
(Initial guesses can be entered for X before selecting F6:SOLVE)

This is useful if you want to quickly try just a few guesses.

However, the ROOT command can be used in a program (for example if you wish to create a program that tries a several guesses (for instance it has an input for both the equation and a list of guesses)).