Using the properties of a parallelogram, can you determine which are parallelograms?

Determine whether the quadrilateral below is a parallelogram. justify/explain your answer (this means back it up! give specific information that supports your decision. writing just "yes" or "no" will result in no credit.)

What is x and y intercepts for y=x+7

How do the definitions, properties, and postulates you've learned about line segments, parallel lines, and angles to define the shapes of polygons