trapezoid
A trapezium or trapezoid.
A trapezium (US) has no sides parallel, while a trapezoid has one set of unequal parallel sides.
A trapezoid is unique because it is a quadrilateral that has one set of parallel sides, and one set that is not parallel.
A trapezoid is unique because it is a quadrilateral that has one set of parallel sides, and one set that is not parallel.
trapzoid
A quadrilateral must have one and only one set of a parallel sides to be a trapezoid.
Only if it is a trapezoid (US usage) with one set of parallel sides, or a parallelogram with both sets of opposite sides parallel. The term quadrilateral only means that the shape has 4 sides.
rhombus
trapezoid
A trapezoid
A parallelogram has two sets of parallel sides.In geometry, a parallelogram is a quadrilateral with two pairs of parallel sides. A quadrilateral with only one set of parallel lines is a trapezoid (UK trapezium).