No, a heptagon cannot be parallel but two heptagons can.A heptagon can be concave.
A square has 2 pairs of opposite parallel lines.
There cannot be parallel lines in any [plane] triangles.
there are 2 sets of parallel lines in a square
A diamond has two pairs of parallel lines.
There can be no convex polygon with three parallel sides. There are concave polygons with 6 or more sides that have three parallel lines.
A triangle can have no parallel lines.
No, a heptagon cannot be parallel but two heptagons can.A heptagon can be concave.
On a quick estimate, I would think 18, 9 for each interior side and another 9 for each interior angle. * * * * * A nonagon has only 9 lines so the above answer is nonsense. With 9 lines you can have at most 4 pairs of parallel lines (and one not parallel to any). Or you could have a concave nonagon with 1 pair, 1 triplet and 1 quartet of parallel lines, or some other combination.
it has too parallel lines!
A pentagon has no parallel lines.
A cone does not have any parallel lines
how many sets of parallel lines are in a triangle
A square has 2 pairs of opposite parallel lines.
Angles cannot be parallel.
A cube has exactly 6 parallel lines.
A cube has exactly 6 parallel lines.