Download number of sides

Polygon review and puzzlers
ÆReview to the classification of polygons:
Is it a Polygon?
Polygons are 2-dimensional shapes. They are made of straight lines, and the shape is "closed" (all the lines connect
up).
Polygon
(straight sides)
Not a Polygon
(has a curve)
Not a Polygon
(open, not closed)
Regular polygons have equal length sides and equal
interior angles. Polygons are named according to their
number of sides.
In the above, those are names to the polygons:
fill in the blank parts.
Name of
triangle
Triangle
Degree of
total angles
180
Degree of
regular angles
60
Quadrilateral
360
90
900
129
1440
144
Pentagon
Hexagon
Heptagon
Names:
number of sides:
hendecagon,
dodecagon,
tetradecagon,
hexadecagon,
heptadecagon,
octadecagon,
enneadecagon,
icosagon
pentadecagon,
11
_____________
13
15
_____________
_____________
_____________
20
_____________
Octagon
Nonagon
Decagon
Do you see a pattern in the calculation of the
total degree of angles of the polygon?
--- (n -2) x 180°
These summation of angles rules, also apply to the irregular polygons, try it out yourself !!!
A point where two or more straight lines meet. Corner.
Example: a corner of a polygon (2D) or of a polyhedron (3D) as shown.
The plural of vertex is "vertices”
Test them out yourself, by drawing diagonals on the polygons.
Here are some fun polygon riddles; could you come up with the answer?
Geometry polygon riddles I:
My first is in shape and also in space; My second is in line and also in place; My third is in point and also in line;
My fourth in operation but not in sign; My fifth is in angle but not in degree; My sixth is in glide but not symmetry;
Geometry polygon riddles II:
I am a polygon all my angles have the same measure all my five sides have the same measure, what general shape
am I?
Geometry polygon riddles III:
I am a polygon. I have two right angles. I have only one pair or parallel sides.
What shape am I?
Geometry polygon riddles IV:
I am a polygon. I have angles that are almost 180 degrees. What shape am I?
Geometry polygon riddles V:
A polygon with four sides. Each line is the same not more. Each angle is right. Can you guess with all your might?
Now you know what is polygon, see if you can apply the knowledge:
How many triangle of different size are there on the left?
_________________________________________________
How many equal lateral quadrilaterals of different size are
there on the left?
Here is a fun puzzle you can solve by apply the these knowledge previously mentioned on
the worksheet, try to decode the message!!!
---- Work purchased from Roxanne Eckenrode @ lulu.com