4
110.Improved Answer:-It is 4
The diagonals of a square for example divides it into 4 isosceles triangles
4
Three: 2, 5, 5 3, 4, 5 and 4, 4, 4
4
4
4
4 are formed
A heptagon has 4 diagonal lines and 7 sides and it has 2 congruent diagonal lines and 2 congruent triangles
4
110.Improved Answer:-It is 4
The diagonals of a square for example divides it into 4 isosceles triangles
4
All triangles have less than 4 lines of symmetry.
See the link under related links below that says "8 Lines 2 Squares 4 Triangles"
6 lines.