Difficulty: Medium
Correct Answer: Incorrect
Explanation:
Introduction / Context:
Regular polyhedra (Platonic solids) are highly symmetric: every face is a congruent regular polygon and the vertex configuration is identical everywhere. Saying “equal regular faces” by itself is not sufficient to declare a polyhedron regular.
Given Data / Assumptions:
Concept / Approach:
The definition of a regular polyhedron has two parts: face regularity and vertex uniformity. Many solids violate vertex uniformity even if their faces are all regular and congruent, making them non-regular.
Step-by-Step Solution:
1) Check that each face is a congruent regular polygon.2) Examine each vertex: the count and order of faces must be identical at every vertex.3) Confirm global symmetry consistent with Platonic solids.4) If vertex configuration differs, the solid is not regular.
Verification / Alternative check:
Compare with known Platonic solids (tetrahedron, cube, octahedron, dodecahedron, icosahedron). Any deviation in vertex configuration disqualifies regularity.
Why Other Options Are Wrong:
“Correct” overlooks the vertex condition; “True for any prism with square faces” is false—prisms do not have identical vertex configurations matching Platonic criteria; “Regardless of vertices” ignores the definition; “Surface area equality” is irrelevant to regularity.
Common Pitfalls:
Assuming face congruence implies overall regularity; neglecting vertex conditions; confusing uniform/semiregular classes with regular ones.
Final Answer:
Incorrect
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