[Tex/LaTex] Multiline item indent

Question

I am currently writing a set of steps for my lecture notes on circles but when the description of the step is too long, becomes multiline, the enumerated environment does not left indents properly as I would like it to be. See my example below at the third step, the word "sides" should be directly below the word "Take":

\documentclass[letterpaper]{article}
\usepackage{fullpage}
\usepackage{amsmath,amssymb,amsthm,enumitem}

\begin{document}
To convert from general form to standard form, we will follow these steps:
\begin{enumerate}[itemindent=1cm,label=\bfseries Step \arabic*.]
  \item Ensure the coefficient of the terms in $x^2$ and $y^2$ are 1 respectively.
  \item Group the terms containing $x$ and $y$ respectively. Move the constant to the RHS.
  \item Take half of the coefficient of the linear terms in both $x$ and $y$, square it and add it to both sides.
  \item Rewrite the result in factored form.
\end{enumerate}
\end{document}

Result:

I am currently reading How to indent second line of an item in list environment? and Leftalign labels with enumitem but I do not quite get how to achieve it with my example in a simple and precise manner. Any help would be highly appreciated.

Answer 1

Instead of setting itemindent, you can change the values for leftmargin and labelindent:

\documentclass[letterpaper]{article}
\usepackage{fullpage}
\usepackage{amsmath,amssymb,amsthm,enumitem}

\begin{document}
To convert from general form to standard form, we will follow these steps:
\begin{enumerate}[leftmargin=*,labelindent=16pt,label=\bfseries Step \arabic*.]
  \item Ensure the coefficient of the terms in $x^2$ and $y^2$ are 1 respectively.
  \item Group the terms containing $x$ and $y$ respectively. Move the constant to the RHS.
  \item Take half of the coefficient of the linear terms in both $x$ and $y$, square it and add it to both sides.
  \item Rewrite the result in factored form.
\end{enumerate}

\end{document}

In fact, if some of your lists will have 10 or more items, the following settings would be preferable:

\documentclass[letterpaper]{article}
\usepackage{fullpage}
\usepackage{amsmath,amssymb,amsthm,enumitem}

\begin{document}
To convert from general form to standard form, we will follow these steps:
\begin{enumerate}[labelwidth=1.5cm,labelindent=10pt,leftmargin=2.2cm,label=\bfseries Step \arabic*.,align=left]
  \setcounter{enumi}{8}% just for the example
  \item Ensure the coefficient of the terms in $x^2$ and $y^2$ are 1 respectively.
  \item Group the terms containing $x$ and $y$ respectively. Move the constant to the RHS.
  \item Take half of the coefficient of the linear terms in both $x$ and $y$, square it and add it to both sides.
  \item Rewrite the result in factored form.
\end{enumerate}

\end{document}

With the help of the layouts package and the following simple code

\documentclass{article}
\usepackage{layouts}

\begin{document}

\begin{figure}
\listdiagram
\caption{List parameters}
\end{figure}

\end{document}

you get a diagram showing the various lengths associated to a list:

the enumitem package adds another parameter \labelindent for the blank space from the margin of the enclosing list/text to the left edge of the label box. Here's the dependencies between the relevant horizontal parameters:

\leftmargin + \itemindent = \labelindent + \labelwidth + \labelsep

Only modifying itemindent changes the indention for the first line of the first paragraph of each \item, and this produces the undesired result in your example code; modifying leftmargin changes the indention for all the lines. Compare the results in this simple example:

\documentclass{article}
\usepackage[showframe]{geometry}
\usepackage{enumitem,lipsum}

\begin{document}

\begin{enumerate}[itemindent=3cm]
\item text
\item \lipsum[2]
\end{enumerate}

\begin{enumerate}[leftmargin=3cm]
\item text
\item \lipsum[2]
\end{enumerate}

\end{document}