Make an ellipse on a background.
- The ratio of the width to the height of the ellipse is 3 to 4.
- The x-coordinate of the mouse controls the width.
- Hit any key to reset the ellipse to 60 by 80.
A point moves on the graph of y = abs(x-90).
- The point starts at (0,90).
- The point goes back to (0,90) after it gets to (200,110).
- The origin is in the lower left (people coordinates, quadrant I).
- Moving the mouse makes the point go faster.
A straight line goes through (50,25) and the point where the mouse is.