A parallelogram is a square in i m sorry both pairs of the opposite sides space parallel .

A parallelogram also has the adhering to properties:

the opposite angles room congruent; opposite sides room congruent; adjacent angles space supplementary;

A rectangle is a parallel with four right angles, so every rectangles are additionally parallelograms and also quadrilaterals. Top top the other hand, not all quadrilaterals and parallelograms space rectangles.

A rectangle has actually all the nature of a parallelogram, plus the following:

The diagonals room congruent.

A rhombus is a parallelogram with 4 congruent sides. The many of rhombus is rhombi . (I love the word.)

A rhombus has actually all the properties of a parallelogram, plus the following:

The diagonals crossing at right angles.

A square have the right to be characterized as a rhombus i m sorry is also a rectangle – in various other words, a parallel with four congruent sides and four appropriate angles.

A trapezoid is a quadrilateral with exactly one pair the parallel sides. (There may be some confusion about this word depending upon which nation you"re in. In India and also Britain, they to speak trapezium ; in America, trapezium usually method a quadrilateral with no parallel sides.)

one isosceles trapezoid is a trapezoid whose non-parallel sides are congruent.

A dragon is a quadrilateral with specifically two bag of adjacent congruent sides. (This an interpretation excludes rhombi. Some textbooks speak a kite has at least 2 pairs of adjacent congruent sides, so a rhombus is a special situation of a kite.)

A scalene square is a four-sided polygon that has actually no congruent sides. Three examples are presented below.

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## Venn diagram of Quadrilateral group

The adhering to Venn Diagram reflects the inclusions and also intersections the the various species of quadrilaterals.