\documentclass{standalone}

\usepackage{tkz-euclide}
\usetkzobj{all}

\usepackage{xepersian}
\settextfont{XB Zar}

\title{ABC-Triangle}
\author{Dalba}
	
\begin{document}
	\begin{tikzpicture}
		\coordinate (O) at (0,0);
		\coordinate (A) at (0,4);
		\coordinate (B) at (2,0);
		\draw (O)--(A)--(B)--cycle;

		\tkzLabelSegment[left=8pt, rotate=90, above=0](O,A){مجاور ضلع}
		\tkzLabelSegment[below right=3pt](O,A){\textit{b}}
		\tkzLabelSegment[below=3pt](O,B){مقابل ضلع}
		\tkzLabelSegment[above=1pt](O,B){\textit{a}}
		\tkzLabelSegment[above right=1pt](A,B){وتر}
		\tkzLabelSegment[below left](A,B){\textit{c}}
		
		\tkzMarkRightAngle[fill=orange, size=.24, opacity=.4](A,O,B)
		\tkzLabelAngle[pos=-.3](A,O,B){$C$}
		
		\tkzMarkAngle[fill=orange, size=.5, opacity=.4](O,A,B)
		\tkzLabelAngle[pos=-.3](B,A,O){$A$}
		
		\tkzMarkAngle[fill=orange,size=.3, opacity=.4](A,B,O)
		\tkzLabelAngle[pos=-.3](O,B,A){$B$}
	\end{tikzpicture}
\end{document}