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.