Examples
align Environment
The following example aligns the given equations at the $\sleftquote\gt\srightquote$ and $\sleftquote\lt\srightquote$ signs of the two equations thanks to the $\sleftquote\&\srightquote$ that occurs just before each. The first equation ends at the $\sleftquote \text{\\\\} \srightquote$.
\begin{align}
\frac{a}{c}&\gt\frac{b}{c}
\qquad\textrm{ if }c\gt0,
a\gt b\\
\frac{c}{a}&\lt\frac{c}{b}
\qquad\textrm{ if }\frac{c}{a}\gt0,
\frac{c}{b}\gt 0,a\gt b
\end{align}