Polygon

Definition

A polygon is a closed, two-dimensional geometric shape composed of straight line segments. The segments are called edges or sides, and the points where two edges meet are called vertices.

5 Must Know Facts For Your Next Test

1. Polygons are classified by the number of sides they have, such as triangles (3 sides), quadrilaterals (4 sides), and pentagons (5 sides).
2. The sum of the interior angles of a polygon with n sides is given by the formula (n-2) * 180 degrees.
3. A regular polygon has all sides and all interior angles equal.
4. The perimeter of a polygon is the sum of the lengths of its sides.
5. Polygons can be convex (all interior angles less than 180 degrees) or concave (at least one interior angle greater than 180 degrees).

Review Questions

• What is the sum of the interior angles of a hexagon?
• How do you determine if a polygon is regular?
• Explain how to find the perimeter of a pentagon.

Related terms

Triangle: A three-sided polygon which includes equilateral, isosceles, and scalene varieties.

Quadrilateral: A four-sided polygon that includes squares, rectangles, trapezoids, and parallelograms.

Perimeter: The total distance around the boundary of a two-dimensional shape.