solve block

The variable ri is undefined.

It would have been better to attach a worksheet to a reply in the original discussion thread rather than posting it as a document. We can't attach worksheets to comments about a document.

I sincerely ask for pardon. I hope you forgive my error.

However, i have discovered my mistaken. Thank you so much.

I am a new user to mathcad, still learning the rudiment of the program. please can you explain to me on what to do if I am to write a code (using iterative approach) rather than using solve block.

I would appreciate it alot.

I sincerely ask for pardon. I hope you forgive my error.

Don't worry about it. I'm just giving you some advice about a better way to post questions. We can reply to a document in the comments, but we can't attach a corrected or example worksheet, which we can do in a discussion.

can you explain to me on what to do if I am to write a code (using iterative approach) rather than using solve block.

I guess the question has to be "why would you want to do that?".

Thank you for your response. My aim was to use iterative approach ( using if, while statement etc) to solve the five equations with four unknown variables. severally, I have tried to write a simple program but seems not working before my friend asked me to use solve block.

That doesn't really answer my question. Why would you want to write your own iterative routine rather than using a solve block? It's more work, and it would be much slower. Mathcad provides solve blocks so that you don't have to do that. You could certainly write such a routine in Mathcad, but it's not quite as simple as just using if and while statements (look up Newton's method for one of the simpler approaches)

Thank you very much. Actually, my supervisor asked me to use iterative approach to develop the mathematical model. +

A solve block is iterative, so you have done what was requested.

Thank you once again for taking out time to respond to my request. More strength to your elbow.