example-2.21.tex

\documentclass{article}

%% Denote paragraphs with vertical space rather than indenting (not critical)
\usepackage{parskip}

%% Support for URL in introductory text (not needed for main example)
\usepackage{url}

%% *** Enable TikZ ***
\usepackage{tikz}

%% *** TikZ library ***
\usetikzlibrary{topaths}

\begin{document}

%% Introductory Text
Example 2.21 from the book\\
\emph{Unlocking LaTeX Graphics: A Concise Guide to Ti$k$Z/PGF and PGFPLOTS}.\\
For more information, visit \url{https://latex-graphics.com}.
\par\bigskip

%% *** START OF EXAMPLE CODE ***
\begin{tikzpicture}
  \path (0.5,0.5) coordinate (A) +(40:3.5) coordinate (B) +(10:3.5) coordinate (C);
  \filldraw[violet, thick, fill=.!50] (B)--(A)--(C) to[bend right=45] (B);
\end{tikzpicture}
%% *** END OF EXAMPLE CODE ***

\end{document}