# Classify and Identify Regular Polygons Worksheets

Naming polygons is one of standard ways in which communicate ideas and objects in the real world. We first have to learn the names of all the objects and then we can start to look inside these structures and make sense of them. To be honest, as you get into geometry, at the high school level, you rarely work with anything other than triangles and quadrilaterals. Occasionally you will come across a pentagon every once and awhile, but not often. It is good for you to learn the names of those structures as you will come across them in really life and in other subject areas. Students can use these worksheets and lessons to learn to name polygons in a variety of orientations.

### Aligned Standard: 5.G.4

- Step-by-Step Lesson- Look at the number of sides, angles, and equivalents to determine the name of the shape.
- Guided Lesson - Here is a nice three pack for you on the enclosed shapes.
- Guided Lesson Explanation - These are ultra simple explanations, not really worth the paper to print it.
- Practice Worksheet - Would you believe that a star is a shape students need to know? I asked this question at a past NCTM conference.
- Matching Worksheet - Match the shapes to their complete descriptions.

- Answer Keys - These are for all the unlocked materials above.

### Homework Sheets

These are great activities to warm up for any major geometry unit.

- Homework 1 - The sides are numbered above 1, 2, 3, and 4. There are four sides. All sides are not same size but opposite sides are equal.
- Homework 2 - Use what you have learned so far, to determine the names and classify all these structures.
- Homework 3 - Four angles numbered by letter A, B, C and D. All boundaries are not same length. All angels are not equal.

### Practice Worksheets

I tried to throw in some really messed up shapes here.

- Practice 1 - The angels are numbered above by letters (A, B, C, D). There are four of them.
- Practice 2 - Write the number of sides, angles, and name of shape.
- Practice 3 - Use what you know about the outlines and corners to help you identify all of these.

### Math Skill Quizzes

Believe it or not, this is one of the more difficult quizzes for students at this level. I never saw that coming!

- Quiz 1 - It has eight sides and eight angles. So the answer is an octagon. Stop sign anyone?
- Quiz 2 - Write the name of shape. I would number everything to help you out.
- Quiz 3 - A good habit to get in when working with these is to number everything and then work on your classification after that.

### How Do You Identify Regular Polygons?

A polygon is a two-dimensional shape with straight sides. As a result, they are all two-dimensional and have both interior and exterior angles, when lines are extended. Some of the most common examples include quadrilaterals, hexagons, pentagons, triangles and so on. There are two types of polygons: Regular and Irregular. In a regular polygon all the angles and sides are equal. This makes them a nice uniform standard. Irregular polygons have either differing angles, sides, or both. This topic in particular will discuss the regular polygons as they are easier to understand.

A regular polygon has two distinct properties: All the angles are equal. If even one of the properties are not just present, it is an irregular polygon. The exterior angles of a regular polygon must add up to 360 degrees. The interior angles and the exterior angles are measured on the same line and therefore, they should add up to 180 degrees.

Naming these shapes is all based on the number of sides that they have. Here are the names of regular polygons based on the number of sides that they have:

3 sides = triangle

4 = quadrilateral

5 = pentagon

6 = hexagon

7 = heptagon

8 = octagon

9 = nonagon

10 sides = decagon

An important thing to note is that these names only apply when the sides and angles are equal. In many cases, if those things shift the names of the shapes change.