# Formatting multiple equations in one displaymath line?

If I want to write multiple equations in the same line in displaymath mode, I would do something like this:

$a + b = c \qquad\text{and}\qquad a^2 + b^2 = c^2$


But I know it's not good to rely on manual spacing. Is there a better way to get the same effect?

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This is not manual spacing and is indeed the recommended way. –  egreg Jan 19 at 15:00

I think your solution is fine, in particular, since it is only one line of equations. Other than that, groups of equations next to each other can be obtained with align, or alignat from the amsmath package. Note however, that these two environments add more space above and below the equations. Compare:

\documentclass{article}

\usepackage{amsmath}

\begin{document}
\hrule
$a + b = c \qquad\text{and}\qquad a^2 + b^2 = c^2$
\hrule

\bigskip

\hrule
\begin{equation*}
\end{equation*}
\hrule

\bigskip

\hrule
\begin{align*}
a + b &= c  &\text{and } a^2 + b^2 &= c^2
\end{align*}
\hrule
\bigskip

\hrule
\begin{alignat*}{2}

my inclination would be, in this case, to put the \quads within the \text; the visual result is the same. also, this is an excellent demonstration of why it's not a good idea to use one of the align structures for a one-line equation, which is (too) often recommended. –  barbara beeton Jan 19 at 16:11