Laurenso
I am trying to show this verylong equation, but I receive a not nice result.
```
\documentclass[12pt,a4paper]{article}
\usepackage{amsthm}
\usepackage{lscape}
\usepackage{mathtools}
\usepackage[paperwidth=20.5cm, paperheight=29cm, left=1.5cm,right=1.5cm,top=1.5cm,bottom=2cm]{geometry}
\begin{document}
\begin{landscape}
\[ \begin{dcases}
x = \frac{c^{2}+m^{2}-n^{2}}{2 c},\\
y =
\frac{a^{2} c^{2}+a^{2} m^{2}-a^{2} n^{2}+b^{2} c^{2}-b^{2} m^{2}+b^{2} n^{2}-c^{4}+c^{2} m^{2}+c^{2} n^{2}-2 p^{2} c^{2}}{2 \sqrt{-\left(a +b -c \right) \left(a -b +c \right) \left(a -b -c \right) \left(a +b +c \right)}\, c}
,\\
\frac{\sqrt{\left(a^{4}-2 a^{2} b^{2}-2 a^{2} c^{2}+b^{4}-2 b^{2} c^{2}+c^{4}\right) \left(a^{4} m^{2}+a^{2} b^{2} c^{2}-a^{2} b^{2} m^{2}-a^{2} b^{2} n^{2}-a^{2} c^{2} m^{2}-a^{2} c^{2} p^{2}+a^{2} m^{4}-a^{2} m^{2} n^{2}-a^{2} m^{2} p^{2}+a^{2} n^{2} p^{2}+b^{4} n^{2}-b^{2} c^{2} n^{2}-b^{2} c^{2} p^{2}-b^{2} m^{2} n^{2}+b^{2} m^{2} p^{2}+b^{2} n^{4}-b^{2} n^{2} p^{2}+c^{4} p^{2}+c^{2} m^{2} n^{2}-c^{2} m^{2} p^{2}-c^{2} n^{2} p^{2}+c^{2} p^{4}\right)}}{a^{4}-2 a^{2} b^{2}-2 a^{2} c^{2}+b^{4}-2 b^{2} c^{2}+c^{4}}
\end{dcases} \]
\end{landscape}
\end{document}
```
How can I get a nice result?
Top Answer
samcarter
Trying to read such a long equation and trying to keep track which terms belong to which parenthesis etc. will probably be hard for your readers.
Personally, I think it would be easier to read if you give names to your two terms and then define the terms separately:
```
\documentclass[12pt,a4paper]{article}
\usepackage{amsthm}
\usepackage{lscape}
\usepackage{mathtools}
\usepackage[paperwidth=20.5cm, paperheight=29cm, left=1.5cm,right=1.5cm,top=1.5cm,bottom=2cm]{geometry}
\begin{document}
\[ \begin{dcases}
x = \frac{c^{2}+m^{2}-n^{2}}{2 c},\\
y =
\frac{a^{2} c^{2}+a^{2} m^{2}-a^{2} n^{2}+b^{2} c^{2}-b^{2} m^{2}+b^{2} n^{2}-c^{4}+c^{2} m^{2}+c^{2} n^{2}-2 p^{2} c^{2}}{2 \sqrt{-\left(a +b -c \right) \left(a -b +c \right) \left(a -b -c \right) \left(a +b +c \right)}\, c}
,\\
\frac{\sqrt{\left(\text{first term}\right) \left(\text{second term}\right)}}{a^{4}-2 a^{2} b^{2}-2 a^{2} c^{2}+b^{4}-2 b^{2} c^{2}+c^{4}}
\end{dcases} \]
\begin{align*}
\intertext{with}
\text{first term} &= a^{4}-2 a^{2} b^{2}-2 a^{2} c^{2}+b^{4}-2 b^{2} c^{2}+c^{4}\\
\intertext{and}
\text{second term} &= a^{4} m^{2}+a^{2} b^{2} c^{2}-a^{2} b^{2} m^{2}-a^{2} b^{2} n^{2}-a^{2} c^{2} m^{2}-a^{2} c^{2} p^{2}+a^{2} m^{4}-\\
&\quad- a^{2} m^{2} n^{2}-a^{2} m^{2} p^{2}+a^{2} n^{2} p^{2}+b^{4} n^{2}-b^{2} c^{2} n^{2}-b^{2} c^{2} p^{2}-b^{2} m^{2} n^{2}+\\
&\quad+b^{2} m^{2} p^{2}+b^{2} n^{4}-b^{2} n^{2} p^{2}+c^{4} p^{2}+c^{2} m^{2} n^{2}-c^{2} m^{2} p^{2}-c^{2} n^{2} p^{2}+c^{2} p^{4}
\end{align*}
\end{document}
```
(replace `first/second term` either with descriptive name or a letter from an alphabet you're not yet using for your equations, so they stand out as "placeholders")