Proving Quadrilaterals are Parallelograms

Alright Euclideans now the real challenge begins.  We have discussed all of the theorems involving what a parallelogram is.  Now we are going to discuss how to prove a 4 sided shape (Quadrilateral) is a parallelogram.  At first thought this may seem, easy and obvious; but if geometry has taught us anything is that we need to truly understand the definitions and theorems and be able to apply them.  I want you to watch the following video and then head to your groups discussion area that you can find by clicking here.

On to the Assessment for the first part of quadrilaterals>>