Double-click on the movie to PLAY.

Click once to PAUSE.

RELOAD the page or double-click to return to the START of the movie.

Method C2

Here we show the transformation operating on a slanting arrow without the grid.
We gradually increase the scale factor, starting at 0 and ending at 2.

We could of course also consider negative scale factors, but we don't do it here.
Instead we present two JAVA worksheets (with and without a grid) that allow you to modify the direction of the invariant line.