# Making systeme use superscripts

I want to make a system of linear equations in LaTeX and I'm using systeme for that. The problem is that I want indices to be superscripted like this:

because that's the notation we use. Yet systeme uses bottom indexing and if I try to do that it gives an error:

$\systeme{x^1 + x^2 + x^3 = 1}$


Package systeme Error: l'inconnue "x_{-1}" a deja ete trouvee dans l'equation !.

Is there any workaround?

• can you supply an example document so people can test answers? (add it to the question in a code block, {} in the editor) – David Carlisle Sep 21 '16 at 10:46

Use the command \syssubstitute (to be found in the systeme documentation), like this:
\documentclass{article}