What do quadrilaterals have in common

Another interesting thing is that the diagonals dashed lines meet in the middle at a right angle. In other words they "bisect" cut in half each other at right angles. A parallelogram has opposite sides parallel and equal in length.

Also opposite angles are equal angles "A" are the same, and angles "B" are the same. A trapezoid called a trapezium in the UK has a pair of opposite sides parallel.

And a trapezium called a trapezoid in the UK is a quadrilateral with NO parallel sides:. An Isosceles trapezoid, as shown above, has left and right sides of equal length that join to the base at equal angles.

The only regular all sides equal and all angles equal quadrilateral is a square. What about kites? Kites are quadrilaterals that can be parallelograms. If their two pairs of sides are equal, it becomes a rhombus, and if their angles are equal, it becomes a square. All rights reserved. Please read our Privacy Policy.

A parallelogram has two parallel pairs of opposite sides. A rectangle has two pairs of opposite sides parallel, and four right angles. It is also a parallelogram, since it has two pairs of parallel sides.

A square has two pairs of parallel sides, four right angles, and all four sides are equal. It is also a rectangle and a parallelogram. A rhombus is defined as a parallelogram with four equal sides.

Is a rhombus always a rectangle? I love that word. A square can be defined as a rhombus which is also a rectangle — in other words, a parallelogram with four congruent sides and four right angles. A trapezoid is a quadrilateral with exactly one pair of parallel sides.

There may be some confusion about this word depending on which country you're in. In India and Britain, they say trapezium ; in America, trapezium usually means a quadrilateral with no parallel sides. An isosceles trapezoid is a trapezoid whose non-parallel sides are congruent.

A kite is a quadrilateral with exactly two pairs of adjacent congruent sides. This definition excludes rhombi. Some textbooks say a kite has at least two pairs of adjacent congruent sides, so a rhombus is a special case of a kite. A scalene quadrilateral is a four-sided polygon that has no congruent sides.