Finding Formula for Circle Area via Parallelogram

Questions to guide your thinking:

1. Play with the sliders a bit. What does each slider do? Suppose the circle has radius r. If we put each slider at its right end (n=80, i=2), the shape we get is nearly, but not quite, a parallelogram. You might even call it a near-rectangle, but I'll call it a "parallelogram". By moving i between 0 and 2, answer these questions: 2. What is the height of the "parallelogram"? 3. What is the width of the "parallelogram"? Now for the punch line: 4. What is the area of the "parallelogram"? 5. What is the area of the circle?