1. Familiarize yourself with the definition of quadrilaterals. Quadrilateral shapes are any twodimensional shapes having four straight sides and four corners. Quadrilaterals are
http://www.ehow.com/how_5244404_learnquadrilatera...

A quadrilateral is a closed plane (2dimensional) shape bounded by four straight lines that meet at four vertices.
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http://pad3.whstatic.com/images/thumb/6/61/FindtheAreaofaQuadrilateralStep1preview.jpg/550pxFindtheAreaofaQuadrilateralStep1preview.jpg.
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Quadrilateral a 4sided polygon. Thanks for using ChaCha and have
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