In geometry, a trapezoid in North American English, or trapezium (/trəˈpiːziəm/) in British English, is a quadrilateral that has at least one pair of parallel See more

There is some disagreement whether parallelograms, which have two pairs of parallel sides, should be regarded as trapezoids. See more

A right trapezoid (also called right-angled trapezoid) has two adjacent right angles. Right trapezoids are used in the trapezoidal rule See more

Given a convex quadrilateral, the following properties are equivalent, and each implies that the quadrilateral is a trapezoid: See more

The ancient Greek mathematician Euclid defined five types of quadrilateral, of which four had two sets of parallel sides (known in English as … See more

Four lengths a, c, b, d can constitute the consecutive sides of a non-parallelogram trapezoid with a and b parallel only when
$${\displaystyle \displaystyle |d-c|<|b-a|<d+c.}$$ See more

The midsegment (also called the median or midline) of a trapezoid is the segment that joins the midpoints of the legs. It is parallel to the bases. Its length m is equal to the average of … See more