Math - 2018-19

3.12 - Polygons

The student will

a)  define polygon;

b)  identify and name polygons with 10 or fewer sides; and

c)  combine and subdivide polygons with three or four sides and name the resulting polygon(s). 

Adopted: 2016


  • So that I can solve problems in real-life and in geometry using representations of polygons
  • So that I can recognize the shapes that are all around me


  • A polygon is a closed plane figure composed of at least three line segments that do not cross. 
  • Polygons may be described by their attributes (e.g., sides and vertices).  Line segments form the sides of a polygon and angles are formed by two line segments coming together at a vertex of a polygon.
  • A rectangle, square, trapezoid, parallelogram, and rhombus are all classified as quadrilaterals. 


The student will use problem solving, mathematical communication, mathematical reasoning, connections and representation to

  • Define polygon. (a)
  • Classify figures as polygons or not polygons. (a)
  • Identify and name polygons with 10 or fewer sides in various orientations:
    • triangle is a three-sided polygon;
    • quadrilateral is a four-sided polygon; 
    • pentagon is a five-sided polygon;
    • hexagon is a six-sided polygon;
    • heptagon is a seven-sided polygon;
    • octagon is an eight-sided polygon;
    • nonagon is a nine-sided polygon; and
    • decagon is a ten-sided polygon. (b)

  • Combine no more than three polygons, where each has three or four sides, and name the resulting polygon. (c) 
  • Subdivide a three-sided or four-sided polygon into no more than three parts and name the resulting polygon(s). (c)


Updated: Aug 22, 2018