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What is 1 + 3?
A geometric shape that has four sides (or edges) and four vertices (or corners).
The interior angles add up to 360°.
A quadrilateral that has exactly one pair of parallel sides
A quadrilateral that has two pairs of parallel sides; opposite sides are parallel and opposite angles are congruent.
A special kind of parallelogram in which all sides are equal.
A special kind of parallelogram in which all angles are right angles.
A special kind of parallelogram in which all sides are equal (equilateral) and all angles are equal (equiangular).