Circle Area

This app is for anyone who wants to understand why the area of a circle is PI R squared.
It doesn’t just tell you that as a fact to be remembered - it demonstrates it in a way that you will never forget.
The app starts out by explaining what the area of a geometric shape is, using the simplest such shape – the rectangle. It allows you to change the width and height and see graphically why the area is simply the width times the height. It then continues to a slightly harder case – the right triangle. A graphical demonstration proves that the area is half the width times the height. The final step is to illustrate graphically how to convert any circle into a right triangle with the same area.