Thank you, Mikael. That is very helpful and much appreciated.

What I now have is:
\startplaceformula
  \startformula
    \startalign
      \NC \[21-(9 - n^2)\NC =□^\prime\]  \NR[eq:1]
      \NC  n^2+12 \NC=□^\prime.          \NR[eq:2]
    \stopalign
  \stopformula
\stopplaceformula
which put the numbers at the right margin,as I wanted.

So how do I get a brace on the left rather than on the right?  Or is there
documentation that explains this?

Alan

On Wed, Oct 9, 2024 at 10:22 AM Mikael Sundqvist <mickep@gmail.com> wrote:

> Hi,
>
> On Mon, Oct 7, 2024 at 11:45 PM Alan Bowen <bowenalan03@gmail.com> wrote:
> >
> > I have the following which works, except for the fact that the equation
> number does not go to the right margin.
> >
> > \startplaceformula
> > \startformula[align=middle, prefix=no]
> > \startcases[distance=2pt]
> > \NC \[21-(9 - n^2)\NC =□^\prime\]\NR
> > \NC\hfill n^2+12 \NC=□^\prime.\NR[eq04]
> > \stopcases
> > \stopformula
> > \stopplaceformula
> >
> > I expect that I have missed something pretty basic here, so any guidance
> will be greatly appreciated.
>
> Maybe I misunderstand you, but I do not think cases is right here.
> Also, are you sure you want to group two equations but only number one
> of them.
>
> If I understand you correctly, I'd try with one of these, depending on
> if citing the group or one of the equations.
>
> \starttext
>
> \startformula
>   \startalign[location=packed,fences=sesac]
>     \NC \[21-(9 - n^2)\NC =□^\prime\]\NR
>     \NC  n^2+12 \NC=□^\prime.        \NR
>   \stopalign
>   \numberhere[eq:foo]
> \stopformula
>
> \startplaceformula
>   \startformula
>     \startalign
>       \NC \[21-(9 - n^2)\NC =□^\prime\]  \NR%[eq:bar-a]
>       \NC  n^2+12 \NC=□^\prime.          \NR[eq:bar-b]
>     \stopalign
>   \stopformula
> \stopplaceformula
>
> \stoptext
>
> /Mikael
>
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