I have 3 formulas which should be aligned at the = sign and numbered (1) to (3).
Seems a simple task but trying both \being{equation} with \begin{split} and \being{align} did not work out. I alwasy struggled with the numbering or wit the alignment. Never got it right.
For example my simple equations good look like:
a = x + y (1)
b = z - k (2)
c = j x (z-k) (3)
= j x b