triangle: no parallel sides square: 2 pairs of parallels (2 opposite sides are parallels) trapezoid must have 1 pair of parallels pentagon: if regular then no parallel, if not regular there can be 1 or 2 pairs of parallels
triangle: none
square: 2 parallels
trapezoid: 1 parallel
pentagon: none ;
A triangle has 0 parallel lines. A square has 2 pairs of parallel lines, a trapezoid has 1 pair, and a pentagon can have 0 or up to 2 pairs depending on its type. Regular pentagons have no parallel lines, while irregular ones may have 1 or 2 pairs.
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