Parallelogram
Pronunciation: /ˌpær.əˈlɛl.əˌgræm/ Explain
Click on the blue points and drag them to change the figure. No
matter where you drag them, the figure is a parallelogram.
Can a parallelogram also be a rectangle? How? Can a parallelogram also be a cube? How?
 Manipulative 1  Parallelogram Created with GeoGebra. 

A parallelogram is a four sided
polygon
whose opposite sides are
parallel.^{[2][3]}

Properties of Parallelograms
Click on the blue points to change the figure. Click on the check boxes to show and hide the properties.
 Manipulative 2  Parallelogram Properties Created with GeoGebra. 

Properties of a parallelogram:
 The opposite angles of a parallelogram are
congruent.
 The opposite sides of a parallelogram are congruent and parallel.
 The diagonals
bisect
each other.
 Each diagonal bisects the parallelogram into two congruent triangles.
 The sums of the angles of a parallelogram is 360° or 2π radians.
 A tessellation of a plane can be created using any parallelogram.
 The area of a parallelogram is A = bh where A is the area,
b is the base and h is the height.

References
 McAdams, David E.. All Math Words Dictionary, parallelogram. 2nd Classroom edition 201501084799968. pg 134. Life is a Story Problem LLC. January 8, 2015. Buy the book
 Hilbert, David. The Foundations of Geometry. pp 28,3335. Translated by Townsend, E. J., Ph. D.. The Open Court Publishing Company. 1950. Last Accessed 12/3/2018. http://www.gutenberg.org/files/17384/17384pdf.pdf. Buy the book
 Stöcker, K.H.. The Elements of Constructive Geometry, Inductively Presented. pp 23, 3233. Translated by Noetling, William A.M, C.E.. www.archive.org. Silver, Burdett & Company. 1897. Last Accessed 12/3/2018. http://www.archive.org/stream/elementsofconstr00noetrich#page/23/mode/1up/search/parallelogram. Buy the book
 Keller, Samuel Smith. Mathematics for Engineering Students, Plane and Solid Geometry. pp 44, 3436, 7273. www.archive.org. D. Van Nostrand Company. 1908. Last Accessed 12/3/2018. http://www.archive.org/stream/firstsixbooksofe00caseuoft#page/44/mode/1up/search/parallelogram. Buy the book
Cite this article as:
McAdams, David E. Parallelogram. 3/26/2019. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/p/parallelogram.html.
Image Credits
Revision History
3/26/2019: Corrected formula for area in manipulative 2. (
McAdams, David E.)
12/21/2018: Reviewed and corrected IPA pronunication. (
McAdams, David E.)
12/1/2018: Removed broken links, updated license, implemented new markup, updated geogebra app. (
McAdams, David E.)
8/28/2018: Corrected spelling. (
McAdams, David E.)
8/7/2018: Changed vocabulary links to WORDLINK format. (
McAdams, David E.)
12/21/2009: Added "References". (
McAdams, David E.)
10/24/2008: Initial version. (
McAdams, David E.)