trapezoid or a trapezium (depending on where you are)
It is a quadrilateral with parallel sides. This includes a square and rectangle, given that a side is parallel with another side.
parallel?
A trapezoid is a 4 sided quadrilateral with one pair of opposite parallel lines of different lengths and the formula for its area is:- 0.5*(parallel side+parallel side)*width or height = area To find the length of a parallel side one of its parallel sides must be given as well as its width and area and so:- Parallel side = (2*area)/(width) - known parallel side
False maybe
Parallelogram and a rectangle
Its 4th side would have to be circular in order to comply with the given requirements
A Trapezium is a quadrilateral with no parallel sides.
trapezoid
Parallelogram and a rectangle
a rectangle, which has two sets of parallel side
An isosceles trapezoid.
A trapezoid would fit the given description which has only 1 pair of parallel sides of different lengths