HP 50g Solve on object?

[iainiain32]

Hi all,
Just purchased a HP50g as I enjoyed using a HP12C and wanted more.

I was trying to programmatically use the SOLVE command and I think the following exemplifies what I am trying to do. Say I have a small program like this:

«
« X 5 + »
'X'
SOLVE
»

The SOLVE command fails on running this program. However, if I use the solver via the menus ("NUM.SLV" and select "1. Solve equation") and enter << X 5 + >> in the equation input the solver correctly returns -5 (screenshot attached). Is there a way I can use the solver in a program on an object <<>> (hopefully I'm using the right terms..)?

As a background on why - I created a program for the value of a call option (which would replace <<X 5 +>> above) and wanted to use the solver to back out the implied volatility (one of the inputs to price of call).

Thank you!