How to interact with the Descartes applet

If the applet becomes smudged, or to reset the initial values at any stage, click "init" (initialise). To change the parameters (here x1, y1 and m) click on the slider up-down arrows. To clear traces, click "clear". To move point P, click-hold and drag the point, or click the x1 and y1 sliders. If you left-click and hold in the applet, the co-ordinates of the point are displayed. To change the scale or "pan" the window, click the sliders at the top of the applet. If active, you can type an equation into the input box and press ENTER.