Which type of triangle has $0$ reflectional symmetries?

• A. Scalene triangle
• B. Equilateral triangle
• C. Isosceles triangle
• D.

Answer: (A)

Verified step by step guidance

1. Understand the concept of reflectional symmetry: A figure has reflectional symmetry if there is at least one line (axis) such that the figure can be folded along that line and both halves match exactly.
2. Recall the types of triangles based on side lengths: Equilateral (all sides equal), Isosceles (two sides equal), and Scalene (all sides different).
3. Analyze the symmetry of an Equilateral triangle: It has 3 lines of symmetry, each passing through a vertex and the midpoint of the opposite side.
4. Analyze the symmetry of an Isosceles triangle: It has exactly 1 line of symmetry, which passes through the vertex angle and bisects the base.
5. Analyze the symmetry of a Scalene triangle: Since all sides and angles are different, there is no line you can fold along to make both halves match, so it has 0 reflectional symmetries.