interior triangles
Triangle
1
Triangle
180
Dodecagon
150
What is the name of this polygon? How do you know?
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This is a heptagon. It has seven sides.
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Quadrilateral
2
Rectangle
360
11 sides (Hendecagon)
11-2=9
9(180)=1620
1620/11=147.2727
What is the name of this polygon? How do you know?
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This is a quadrilateral. It has 4 sides.
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Pentagon
3
Nonagon
1260
13 sided figure
13-2=11
11(180)=1980
1980/13=152.3076
What is the name of this polygon?

This is a regular pentagon.

Hexagon.
4
Decagon
1440
50 sided figure
50-2=48
48(180)=8640
8640/50=172.8
Name the quadrilaterals: a, b, and d.
BONUS 200: Name all the quadrilaterals.

(a) rectangle, (b) square, (c) parallelogram; (d) rhombus and (e) kite

Nonagon
7
n-gon
(n-2)*180
102 sided figure
102-2=100
100(180)=18000
18000/102=176.47
What are the names of these triangles?

Top: Equilateral triangle, Right-angled triangle, Isosceles triangle
Bottom: Scalene triangle, Acute triangle, Obtuse triangle
