transformation of an equation

bin mir nicht sicher, würde das aber so übersetzen

Lösen/Umstellen einer Gleichung nach x.
To solve an equation for x.

Anstelle von "umstellen einer Gleichung" sagt man auch "lösen einer Gleichung". Zumindest verwenden meine Matheprogramme ausschließlich den Englischen Begriff "to solve".

Bin aber auch kein Englisch-Fachmann.

to rearrange it

rearrange the equation to solve for ...

http://books.google.co.uk/books?id=jfdCeWyMST...

I'm more familiar with "rearrange" than with "transpose".

To me, "rearrange" is the fall-back option. It's definitely the write word for equations.

The "solve for" thing is applicable if you're trying to get something specific on one side of the equation (e.g. "solve for x" means rearrange the equation to get: x= {bla bla}).

But you can rearrange the equation without solving it. In fact, "solving for x" often involves several steps, in which the equation continues to be rearranged until x appears alone on one side.

write = right, having a sudden bout of acoustic dyslexia here :)