MWE:
\documentclass{article}
\usepackage{amsmath,amsfonts,amssymb,amsthm}
\begin{document}
\begin{gather*}
y=3x-6 --- {1}\\
y=-x+5 --- {2}\\
\end{gather*}
\end{document}
Picture:
How do I join the three dashes?
I tried \rule
and \line
but they only give me a line aligned to the bottom of the text.
Best Answer
If you want rule:
Depending on how long the rule should be, you may change the dimension or simply use
\text{---}
..