GeoGebra is an interactive geometry, algebra, statistics and calculus application, intended for learning and teaching mathematics and science from primary school to university level.
“Finding Area by Decomposing and Rearranging” from IM Grade 6 by Open Up Resources and Illustrative Mathematics. Licensed under the Creative Commons Attribution 4.0 license.
Use any GeoGebra tool(s) in the app above to clearly show how you know the quadrilateral you just formed is a parallelogram. Be sure to fully explain your reasoning!