A square, rectangle, rhombus, trapezoid, and parallelogram are all quadrilaterals. They all have four side but have certain conditions to be defined by separate names. Both a rhombus and square require sides of equal length and parallel. read more

Quadrilaterals are closed figures with four sides, and parallelograms are closed figures with two pairs of sides, each pair parallel. A pair is two sides, and so 2 sides * 2 sides = 4 sides on a parallelogram, meaning that parallelograms are just a subset of quadrilaterals that have opposite, parallel sides. read more

Parallelograms are quadrilaterals with opposite sides equal, and parallel. Not all sides are equal though. Rectangles are Parallelograms that have all angles equal (90 degrees for each of the 4) Squares are Rectangles that have all sides equal. So working your way up the logic ladder, they are also Parallelograms, and Quadrilaterals. read more

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Why is a square a parallelogram?

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If they would, for Example, praise the Beauty of a Woman, or any other Animal, they describe it by Rhombs, Circles, Parallelograms, Ellipses, and other geometrical terms ...Source: quotemaster.org