Rotation of Axes

\setlength{\unitlength}{1mm}
\begin{picture}(93,46)
  \put( 0,14){\vector(1,0){60}} 
  \put(61,13){$x$}
  \put(20,4){\vector(0,1){37}} 
  \put(19,43){$y$}
  \put(50,34){\circle*{2}} 
  \put(52,35){$P$}
  \multiput(20,34)(4,0){8}{\line(1,0){2}} 
  \put(14.5,33.5){$y_P$}
  \multiput(50,14)(0,4){5}{\line(0,1){2}} 
  \put(48,11){$x_P$}
  \put( 2,8){\vector(3,1){56}} 
  \put(59,26.5){$x'$}
  \multiput(50,34)(1.9,-5.7){2}
    {\line(1,-3){1.2}}     
  \put(52,22){$x_P'$}
  \multiput(50,34)(-5.8,-1.933){6}
    {\line(-3,-1){3.6}} 
  \put(12,21){$y_P'$}
  \put(22,8){\vector(-1,3){10.5}} 
  \put(10,41){$y'$}
\end{picture}