That will depend on what type of triangle it is because an equilateral triangle has 3 lines of symmetry whereas an isosceles triangle has only 1 line of symmetry and other triangles have no lines of symmetry.
square
An equilateral triangle has three lines of symmetry. Each line of symmetry passes through a vertex and bisects the opposite side, resulting in three equal parts.
2 lines of symmetry
A nephroid has 2 lines of symmetry.
A parallelagram can be a square, which has four lines of symmetry or a rectangle which has two lines of symmetry but the generic parallelagram has zero lines of symmetry
square
An equilateral triangle has three lines of symmetry. Each line of symmetry passes through a vertex and bisects the opposite side, resulting in three equal parts.
2 lines of symmetry
it has five lines of symmetry
A nephroid has 2 lines of symmetry.
Equilateral Triangles (3 lines of symmetry)Rectangles (at least 2 lines of symmetry)Squares (4 lines of symmetry)Rhombuses (at least 2 lines of symmetry)Any regular polygon (at least 5 lines of symmetry)
it has no lines of symmetry
A parallelagram can be a square, which has four lines of symmetry or a rectangle which has two lines of symmetry but the generic parallelagram has zero lines of symmetry
There is no such thing as 8 lines of symmetry. A circle, for example, has infinitely many lines of symmetry.
A decagon need not have any lines of symmetry. It can also have 1 or 10 lines of symmetry.
5 lines
Lines of symmetry are 2 dimensional. Planes of symmetry are 3D.