Before you begin: Feel free to move this quadrilateral's vertices (corners) wherever you'd like. You can control the size of the red exterior angle by using the red slider. You can control the size of the blue exterior angle by using the blue slider. This applet works best if this quadrilateral is kept convex. If you don't remember what this means, click here for a refresher. Interact with the applet for a minute or two. Then answer the question that follows.