standard_description: Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.
problem_activity: Task
Suppose $\overline{AB}$ is a line segment and $D$ is a point not on $\overline {AB}$ as pictured below:
[IMG]
Let $C$ be the point so that $|CD| = |AB|$, $\overleftrightarrow{CD}$ is parallel to $\overleftrightarrow{AB}$, and $ABCD$ is a quadrilateral.
Draw a picture of this situation and
show that $ABCD$ is a parallelogram.


aligns: no