HP 50g

[DavidM]

Here's one way:

For purposes of this example, I'm starting with no variables or equations defined, with the path set to HOME.




Activate the numeric solver by pressing RS-7 (right shift followed by 7), then ENTER to specify item 1.




Activate the Equation Writer with RS-' (right shift followed by '/O/MTRW/EQW).




I'll use a simple equation for this example.




Pressing ENTER saves that equation into the solver's EQ variable and creates the corresponding variables.




At this point I realize that I was too hasty when entering the equation and need to change it slightly to reflect a minor detail that was initially overlooked. If field "Eq" is selected by pressing <up arrow>, your inclination may be to press RS-' as was initially done, but that simply starts a new equation from scratch. Pressing the EDIT soft menu key will bring the algebraic form of the equation to the command line, but I believe that is what you are trying to avoid.

Making sure that the Eq field is still highlighted, press the "NXT" button to show the 2nd row of the soft menus.




Now, press the "CALC" soft menu key.




This gives you a stack display that is similar to what you would normally see if not in the numeric solver environment. To use the Equation Writer, simply press the <down arrow> key.


Press ENTER when done editing, then the "OK" soft menu to update the equation for the solver.




There are other ways, of course, but this is a fairly straightforward method that keeps you from having to leave the solver environment and then manually editing the variables/equation.