POLYGONS
Higher Tier
POLYGONS
Number of sides
polygons
Name
3
Triangle
4
Quadrilateral
5
Pentagon
6
Hexagon
7
Heptagon
8
Octagon
9
Nonagon
10
Decagon
©RSH 13 April 2010
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POLYGONS
Higher Tier
INTERIOR ANGLES OF A POLYGON
REMEMBER

The sum of the interior angles of a triangle is 180°.

The sum of the interior angles of a quadrilateral (e.g. a square or rectangle) is 360°.
To find the sum of the interior angles of any polygon, follow these steps:
Step 1
From one vertex, draw all the
diagonals to divide the polygon into
triangles.
Step 2
Find the sum of the angles in all of
these triangles.
Octagon
In this octagon, there are 6 triangles.
Therefore the sum of the interior
angles is 6  180° = 1080°.
And in this 12 sided polygon
Number of triangles =
Sum of the interior angles =
polygons
©RSH 13 April 2010
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POLYGONS
Higher Tier
EXTERIOR ANGLES OF A POLYGON

The sum of the exterior angles of any polygon is 360°
LOGO
REPEAT 3 [FD 100 RT 360/3]
Draws an equilateral triangle
REPEAT 4 [FD 100 RT 360/4]
Draws a square
REPEAT 5 [FD 100 RT 360/5]
Draws a regular pentagon
REPEAT ? [FD 100 RT 360/?]
Draws a regular octagon
polygons
©RSH 13 April 2010
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