Prove that any four vertices of a regular pentagon are concyclic.

Explanation

To prove that any four vertices of a regular pentagon are concyclic, we can follow these steps:

### Step 1: Define the Regular Pentagon
Let the vertices of the regular pentagon be labeled as \( A, B, C, D, E \). In a regular pentagon, all sides are equal and all interior angles are equal.

### Step 2: Select Four Vertices
Choose any four vertices of the pentagon. For example, let’s choose vertices \( A, B, C, \) and \( D \).

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