Download Ch 2.4 notes

Ch 2.4 notes
September 16, 2016
2.4 - Angle Properties in
Polygons
Objective:
1.3 Generalize, using inductive reasoning, a rule for the relationship between the sum of the interior angles and the number of sides (n) in a polygon, with or without technology.
Soccer ball, first
used in 1970
World Cup
Carbon molecule
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Ch 2.4 notes
September 16, 2016
Using a ruler and a protractor fill in the table.
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Ch 2.4 notes
September 16, 2016
What is the relationship between the sum of
the measure of the interior angles and the
number of sides of the polygon?
Hint: use the number 180!!!
Convex polygon: a polygon in which each
interior angle measures less than 180o .
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Ch 2.4 notes
September 16, 2016
Jacob is building a gazebo with a regular
hexagon shape. At what angle will Jacob
need to build each interior angle of his
gazebo?
Determine the measure of each interior angle
of a regular 15-sided polygon (a pentadecagon).
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Ch 2.4 notes
September 16, 2016
A floor tiler designs custom floors using tiles
in the shape of regular polygons. Can the tiler
use congruent regular octagons and congruent
squares to tile a floor, if they have the same
side length?
Can a tiling pattern be created using
regular hexagons and equilateral triangles
that have the same side length? Explain.
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Ch 2.4 notes
September 16, 2016
Determine the sum of the measures of the interior angles of a regular dodecagon.
Determine the measure of each interior angle of a regular dodecagon.
N
O
M
P
L
Q
W
R
S
V
U
T
Determine the sum of the measures of the angles in a 20­sided convex polygon.
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Ch 2.4 notes
September 16, 2016
The sum of the measures of the interior angles of an unknown polygon is 3060°. Determine the number of sides that the polygon has.
Throughout our lesson today, when did we
use inductive reasoning? When did we use
deductive reasoning?
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Ch 2.4 notes
September 16, 2016
Evil bonus ­ what is the sum of the angles?
h
g
a
f
b
c
e
d
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