trapezoids
Geometric shapes that have only one pair of parallel sides include trapezoids (or trapeziums in some regions) and certain types of irregular quadrilaterals. In a trapezoid, the two non-parallel sides are not equal in length and can converge or diverge. These shapes are characterized by their unique angle and side properties, distinguishing them from other quadrilaterals.
a trapezoid
A shape with one or more parallel sides is called a trapezoid (or trapezium in some regions). In a trapezoid, at least one pair of opposite sides is parallel. Other shapes, like rectangles and parallelograms, also have parallel sides. These characteristics are key in distinguishing these geometric figures.
rectangular
rhombus
A square
Any polygon with four or more sides can have a pair of parallel sides. It is also possible to to have non-polygonal shapes - eg a cigar-shape - that has parallel sides.
Not all four-sided shapes have one pair of parallel sides. For example, a rectangle and a trapezoid can have one pair of parallel sides, but a general quadrilateral does not necessarily have any parallel sides. Shapes like rhombuses and squares have two pairs of parallel sides, while irregular quadrilaterals may have none. Thus, the presence of parallel sides depends on the specific type of four-sided shape.
The first geometric shape that comes to mind with no perpendicular sides is a triangle.
Any polygon, other than a triangle, can have one pair of parallel sides.
trapezoidTrapezoid.
You need at least one pair of parallel sides. Most trapezoids have that.