Regular or Irregular Polygon

Regular or Irregular Polygon

A polygon is regular when all sides are the same length and all angles are the same size. If even one side length or one angle does not match the others, the polygon is irregular.

How to decide

1. Check the sides: compare every side length.
2. Check the angles: compare every interior angle.
3. Classify the polygon:
   • Regular: all sides equal and all angles equal.
   • Irregular: not all sides equal or not all angles equal.

Good strategy

If measurements are given, list them in order and look for differences. For some shapes, side lengths alone are enough to rule out regularity, because a regular polygon must satisfy both conditions.

Final check

Before answering, make sure your conclusion matches the definition:

• If everything matches, say regular.
• If anything differs, say irregular.

When asked to simplify the final answer, give only the simplest classification unless the exercise asks for an explanation.