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5th grade

Unit 16: Lesson 3

Properties of shapes

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Polygons review

CCSS.Math:

Google Classroom

Review the term polygon and name polygons with up to 8 sides. Then, try some practice problems.

What is a polygon?

A polygon is a closed figure with at least 3 straight sides.

Practice set 1

Problem 1A

Is the following figure a polygon?

Want to learn more about recognizing shapes? Check out this video.

Identifying polygons

Polygons can be named by their number of sides.

Number of sides	Name
3	Triangle
4	Quadrilateral
5	Pentagon
6	Hexagon
7	Heptagon
8	Octagon

Practice set 2

Problem 2A

Which of these shapes are quadrilaterals?

Want to try more problems like this? Check out this exercise

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Want to join the conversation?

Faaty
Posted 4 years ago. Direct link to Faaty's post “What is the difference Be...”
What is the difference Between a Circle, Ellipse And an oval .
(7 votes)
Answer
- Sebastian Fursov
  Posted 4 years ago. Direct link to Sebastian Fursov's post “Well, a circle is identic...”
  Well, a circle is identical all around it, an ellipse changes due to it's diameter, and an oval, similar to an ellipse, is never identical all around. Hope this helps!
  (2 votes)
bh4troy
Posted 6 years ago. Direct link to bh4troy's post “What's a polygon”
What's a polygon
(0 votes)
Answer
- Tgeneral2001
  Posted 6 years ago. Direct link to Tgeneral2001's post “A polygon is made of any ...”
  A polygon is made of any three straight sides with the lines all connected to each other, as well as not overlapping and meeting at the ends of the lines.
  (2 votes)
Trixie Tang
Posted 6 years ago. Direct link to Trixie Tang's post “Actually does anyone know...”
Actually does anyone know the name of a 20-sided shape?
(4 votes)
Answer
- Sujal J.👍
  Posted 6 years ago. Direct link to Sujal J.👍's post “A 20 - sided shape is cal...”
  A 20 - sided shape is called a icosagon. To learn about other shapes with a lot of sides go to:
  https://sngweb.com/education/formula/geometry/polygon_name.html
  (0 votes)
Mason Howe
Posted 6 years ago. Direct link to Mason Howe's post “Is Nonagon Belong In A Po...”
Is Nonagon Belong In A Polygon?
(5 votes)
Answer
- G junior
  Posted 6 years ago. Direct link to G junior's post “Yes a nonagon is a polyg...”
  Yes a nonagon is a polygon, one with nine sides and angles.
  (4 votes)
AwesomeYP
Posted 6 years ago. Direct link to AwesomeYP's post “3 dimensional octagon is ...”
3 dimensional octagon is called a octahedron
(7 votes)
Answer
- Billy LanPowell
  Posted 6 years ago. Direct link to Billy LanPowell's post “A three dimensional octag...”
  A three dimensional octagon is a octagonal prism. An octahedron is a square pyramid stacked on top of another one, and it has 8 sides.
  (3 votes)
holdenis#1
Posted 5 years ago. Direct link to holdenis#1's post “what would a ten sided sh...”
what would a ten sided shape be called?
(2 votes)
Answer
- Caleb
  Posted 5 years ago. Direct link to Caleb's post “Decagon. In geometry, a d...”
  Decagon. In geometry, a decagon is a ten-sided polygon or 10-gon
  (3 votes)
ULTIMATEGUYZ
Posted 5 years ago. Direct link to ULTIMATEGUYZ's post “What is a 24-sided shape ...”
What is a 24-sided shape called?
(0 votes)
Answer
- stella stovall
  Posted 3 years ago. Direct link to stella stovall's post “it is a 24-gon because a ...”
  it is a 24-gon because a shape with more than 10 sides is named as its sides.
  (3 votes)
ℙ𝕒𝕥𝕣𝕚𝕔𝕜
Posted 3 years ago. Direct link to ℙ𝕒𝕥𝕣𝕚𝕔𝕜's post “What is a fifty sided sha...”
What is a fifty sided shape called?
(4 votes)
Answer
nairjeevans
Posted 3 years ago. Direct link to nairjeevans's post “if it is not closed then ...”
if it is not closed then it isnt a polygon, right?
(3 votes)
Answer
- Jaylightningstrike7
  Posted a month ago. Direct link to Jaylightningstrike7's post “correcto!1”
  correcto!1
  (1 vote)
mirandacarlosm6
Posted 5 years ago. Direct link to mirandacarlosm6's post “is there a shape that has...”
is there a shape that has 11 sides?
(4 votes)
Answer
- spalathumveedu
  Posted a month ago. Direct link to spalathumveedu's post “yes there is hendagon!”
  yes there is hendagon!
  (1 vote)