6.5. Parallelogram Classification http://www.ck12.org
6.5 Parallelogram Classification
Here you’ll learn what properties differentiate the three special parallelograms: rhombuses, rectangles, and squares.
What if you were designing a patio for you backyard? You decide to mark it off using your tape measure. Two sides
are21 feetlong and two sides are28 feetlong. Explain how you would only use the tape measure to make your
patio a rectangle. After completing this Concept, you’ll be able to answer this question using properties of special
parallelograms.
Watch This
MEDIA
Click image to the left for more content.CK-12 Foundation: Chapter6ParallelogramClassificationA
MEDIA
Click image to the left for more content.Brightstorm:Rectangle and Square Properties
MEDIA
Click image to the left for more content.Brightstorm:RhombusProperties
Guidance
Rectangles, rhombuses(the plural is also rhombi) andsquaresare all more specific versions of parallelograms.
Rectangle Theorem:A quadrilateral is a rectangle if and only if it has four right (congruent) angles.
Rhombus Theorem:A quadrilateral is a rhombus if and only if it has four congruent sides.
Square Theorem:A quadrilateral is a square if and only if it has four right angles and four congruent sides.
From the Square Theorem, we can also conclude that asquare is a rectangle and a rhombus.