\documentclass{article}
\usepackage{argoclp}
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\def_{\_}

\def\d{{\fontencoding{T1}\selectfont\dj}}

\def\D{{\fontencoding{T1}\selectfont\DJ}}

\setlength{\textheight}{22cm} 
\newtheorem{axiom}{Axiom}
\newtheorem{theorem}{Theorem}
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\begin{document}

\title{High school geometry theorems}
\author{Hilbert's axiomatic system.\\
Formalized by: Sana Stojanovic Djurdjevic \\
Proved by: ArgoGeoChecker.}
\date{30.03.2018.}
\maketitle

\begin{theorem}[th_7_01.]
Assuming that $A \in t$ and $B \in t$ and $C \in t$ and $D \in t$ and $bet(A, D, B)$ and $bet(A, D, C)$ it holds that $\neg bet(B, D, C)$.
\end{theorem}

\hrule 

\end{document}
