Gambar akhir

\draw[red!50,thin](B)--(Q) (D)--(R) (A)--(S);
\draw (P)--($(B)!-3.5cm!(P)$) (E)--(D)--(A)--(C) node[above] {$C$}--(B);
\draw (B) circle (1);
\draw let \p1=($(A)-(C)$),\n1={veclen(\x1,\y1)}
  in (C) circle (\n1);
\foreach \t in {A,B,C,D,E}
\fill (\t) circle (1.5pt);