Question

The number of planes of symmetry in a tetrahedron is

• A. 9
• B. 6
• C. 4
• D. 3

Hint:

Regular polyhedra have well-defined symmetry properties.
- Cube: 9 planes of symmetry.
- Tetrahedron: 6 planes of symmetry.
- Octahedron: 9 planes of symmetry.

Answer 1

The Correct Option is B

Step 1: Recall the geometry of a tetrahedron.
A regular tetrahedron has 4 triangular faces, 4 vertices, and 6 edges. Symmetry elements include planes, axes, and a center of symmetry. Step 2: Understanding planes of symmetry.
A plane of symmetry divides the figure into two identical mirror-image halves.
In a regular tetrahedron: - Each plane of symmetry passes through an edge and the midpoint of the opposite edge. Step 3: Counting the planes.
- For a tetrahedron, there are \(\mathbf{6}\) such symmetry planes.
Thus, the total number of planes of symmetry is 6. Final Answer: \[ \boxed{6} \]