Use the contol buttons at the bottom to drive the dart around.
You will see that the red 'locus point' draws a line as the dart moves.
When you are used to using the control buttons,
press the reset button and try to draw a square.
Press reset again and try other shapes, a triangle, a house, a hexagon...
Press reset and drag the locus point to the dart's wing tip.
Drag the other one that was underneath to the other wing tip.
Drive the dart around to see what paths are generated.
Press reset and try experimenting with different positions for the locus points.
For example, try the nose and centre of the dart.
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