\input{preamble-standalone.ltx}
\begin{document}

% Ex. No. 86 (Section 12.2.3 : Example of Andrew Mertz)

\begin{tikzpicture}[scale=.5]
 \tkzDefPoint(100:8){A}\tkzDefPoint(50:8){B}
 \tkzDefPoint(0,0){C} \tkzDefPoint(0,4){R}
 \tkzDrawCircle(C,R)
 \tkzDefTangent[from = A](C,R)  \tkzGetPoints{D}{E}
 \tkzDefTangent[from = B](C,R)  \tkzGetPoints{F}{G}
 \tkzDrawSector[fill=blue!80!black,opacity=0.5](A,D)(E)
 \tkzFillSector[color=red!80!black,opacity=0.5](B,F)(G)
 \tkzInterCC(A,D)(B,F) \tkzGetSecondPoint{I}
 \tkzDrawPoint[color=black](I)
\end{tikzpicture}

\end{document}