How it works ?
- Creation of this applet was inspired by a tweet from Marilyn Burns that was retweeted by Dan Meyer.
- Suppose a rectangle has a length that is twice its width. A diagonal is drawn from one vertex to the opposite vertex. In addition, 2 segments are drawn from one endpoint of this diagonal to the midpoints of the sides of the rectangle not adjacent that vertex.
- These 3 segments cause the rectangle to be split into 4 triangles of equal area.
- Feel free to change the size of the rectangle by moving the BIG WHITE POINT at any time.
- How do the dynamics of this applet informally suggest these 4 triangles have equal area?
- How can you formally prove what this applet informally illustrates?