It depends on the dimensions of the triangle, some have 0, but no triangle will ever have more than 3 lines of symmetry.
A triangle can have no parallel lines.
A nephroid has 2 lines of symmetry.
it has five lines of symmetry
2 lines OF SYMMETRY
10 lines of symmetry
4 Lines of symmetry
2 lines of symmetry
2 lines of symmetry
It has 2 lines of symmetry.
no lines of symmetry
5 lines