Naming Polygons
Polygons are named by the number of their sides using Greek and Latin prefixes: tri- means 3 sides (triangle), quad- means 4 sides (quadrilateral), penta- means 5 sides (pentagon), hexa- means 6 sides (hexagon), hepta- means 7, octa- means 8 (octagon), nona- means 9, and deca- means 10. In Grade 6 Saxon Math Course 1 (Chapter 6: Geometry and Number Operations), students use these prefixes to identify and name any polygon and recognize that the number of sides equals the number of angles. A polygon must be a closed flat shape with all straight sides.
Key Concepts
Property Polygons are named by the number of sides they have. The prefix of a polygon's name tells how many angles and sides the polygon has: tri means 3, quad means 4, and penta means 5.
Examples A shape with six sides is called a hexagon, because the prefix hexa means six. A polygon with four sides is called a quadrilateral, which is the general name for all four sided shapes. Since penta means five, a pentagon is a polygon that always has exactly 5 sides.
Explanation Naming polygons is like learning a secret code where the first part of the word reveals its identity! The prefix, like 'octo ' or 'hexa ', tells you exactly how many sides and corners the shape has. Master the prefixes, and you'll be a polygon naming ninja in no time!
Common Questions
How are polygons named?
Polygons are named by the number of sides using prefixes: 3 sides = triangle, 4 = quadrilateral, 5 = pentagon, 6 = hexagon, 8 = octagon, 10 = decagon.
What prefix means 5 in polygon names?
Penta- means 5. A pentagon has 5 sides and 5 angles.
How many sides does a hexagon have?
A hexagon has 6 sides. The prefix hex- means 6.
What is the relationship between the number of sides and angles in a polygon?
Every polygon has the same number of angles as sides. A pentagon has 5 sides and 5 angles; an octagon has 8 sides and 8 angles.
What makes a shape a polygon?
A polygon is a closed flat shape made entirely of straight line segments. Circles and shapes with curved sides are not polygons.