There are plenty of different type of quadrilaterals, yet all have several things in common: every one of them have four sides, are coplanar, have two diagonals, and the sum of their four interior angles amounts to 360 degrees. This is exactly how they room alike, yet what renders them different?


We know plenty of quadrilaterals through their distinct shapes and properties, like squares. Remember, if friend see the word quadrilateral, the does no necessarily mean a figure with one-of-a-kind properties prefer a square or rectangle! In indigenous problems, be cautious not to assume that a quadrilateral has parallel sides or same sides uneven that is stated.

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Special Quadrilaterals


A parallelogram has two parallel bag of the contrary sides.


A rectangle has actually two pairs of opposite political parties parallel, and four ideal angles. It is also a parallelogram, since it has two bag of parallel sides.


A square has two bag of parallel sides, 4 right angles, and also all four sides are equal. The is likewise a rectangle and a parallelogram.


A rhombus is defined as a parallel with 4 equal sides. Is a rhombus constantly a rectangle? No, since a rhombus walk not need to have 4 ideal angles.
Trapezoids only have one pair that parallel sides. It"s a kind of quadrilateral the is not a parallelogram. (British name: Trapezium)


Kites have two pairs of surrounding sides that are equal.

We have the right to use a Venn diagram to assist us group the species of quadrilaterals.


A Venn diagram uses overlapping circles to show relationships in between groups the objects. Every "quadrilaterals" can be separated into three sub-groups: basic quadrilaterals, parallelograms and also trapezoids.

Is a rectangle constantly a rhombus? No, because all 4 sides the a rectangle don"t have to be equal. However, the to adjust of rectangles and also rhombuses perform intersect, and their intersection is the collection of squares—all squares are both a rectangle and also a rhombus.

We can put squares in the intersection of the 2 circles.

From this diagram, you have the right to see the a square is a quadrilateral, a parallelogram, a rectangle, and a rhombus!

Is a trapezoid a parallelogram? No, because a trapezoid has only one pair that parallel sides. That is why we must present the set of trapezoids in a different circle ~ above the Venn diagram.

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What about kites? Kites are quadrilaterals the can it is in parallelograms. If their 2 pairs that sides room equal, it becomes a rhombus, and if your angles space equal, it becomes a square.

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