# Special Quadrilateral: Theorem 4

- Author:
- Tim Brzezinski

- Topic:
- Parallelogram, Quadrilaterals

Interact with the applet below for a few minutes.
Then, answer the questions that follow.
Feel free to move the BIG WHITE POINTS anywhere you'd like!
You can also adjust the size of the green angle by using the slider.

## 1.

What conditional (if-then) statement can you write based upon the logical order of dynamic phenomena (i.e. actions) you observed in this applet?

## 2.

Write a 2-column, paragraph, or coordinate-geometry proof of the conditional statement you wrote for (1) above.