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\begin{document}

%-------------------------------------------------------------------

\section*{angle}

\hypertarget{angle}{}\section*{{Angle}}\label{angle}

An \textbf{angle} is a measure of \emph{turn}. More precisely, the angle formed between two [[lines]] at their intersection point is a measure of how much one line should be rotated about that point to lie along the second line.

Angles can be signed or unsigned, if signed then the convention is that positive angles are anti-clockwise and negative angles clockwise.

There are different units when measuring angles:

\begin{itemize}%
\item \textbf{degrees} a full turn is $360^\circ$
\item \textbf{radians} a full turn is $2\pi$ radians

\end{itemize}
There are several types of angle:

\begin{itemize}%
\item An \textbf{acute} angle is an angle between no turn and a quarter turn
\item A [[right-angle]] is a quarter of a turn
\item An \textbf{obtuse} angle is an angle between a quarter turn and a half turn
\item A \textbf{reflex} angle is an angle between a half turn and a full turn

\end{itemize}
[[!redirects acute]] [[!redirects obtuse]] [[!redirects reflex]] [[!redirects acute angle]] [[!redirects obtuse angle]] [[!redirects reflex angle]] [[!redirects acute angles]] [[!redirects obtuse angles]] [[!redirects reflex angles]] [[!redirects angles]]



\end{document}