What shape is this? Please help.

Answer:
A parallelogram
Step-by-step explanation:
One of the definitions of a parallelogram is that opposite sides are equal. In this case, 6 = 6 and 4 = 4 so it is a parallelogram.
On the other hand, if you are talking about the shapes making up the parallelogram, they are triangles because they have 3 sides.