Download 7.1 - Each angle.notebook

7.1 ­ Each angle.notebook
January 31, 2017
Bellringer: What are the sums of the exterior angles and the interior angles of an nonagon?
Jan 30­11:33 AM
Jan 31­1:02 PM
What do regular polygons allow us to do?
Polygon Formulas In a regular polygon, the measure of each interior angle is defined as the sum of all the angles divided by the number of sides (which is the same as the number of angles).
a.) What is the sum of the angles in a regular pentagon?
Regular Pentagon
Measure of Each Interior Angle
b.) What is the measure of each angle in a regular pentagon?
c.) What is the sum of the exterior angles in a regular pentagon?
d.) What is the measure of each exterior angle in a regular pentagon?
Jan 30­11:24 AM
In a regular polygon, the measure of each exterior angle is defined as the sum of all the exterior angles divided by the number of sides.
Measure of Each Exterior Angle
Jan 30­11:24 AM
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7.1 ­ Each angle.notebook
Summary of all Formulas
#1 and 2 apply to all polygons
January 31, 2017
Regular Polygons
Examples
1.) Sum of Interior Angles 1.) The trampoline to the right is a regular dodecagon.
2.) Sum of Exterior Angles a.) Find the measure of each interior angle.
#3 and 4 apply to only regular polygons
3.) Measure of Each Interior Angle b.) Find the measure of each exterior angle.
4.) Measure of Each Exterior Angle Jan 30­11:15 AM
Jan 30­11:22 AM
Examples Examples 4.) Find the name of the polygon whose angles add up to 1080o.
2.) Find the sum of the angles in a decagon.
3.) Find the measure of each internal angle in a regular heptagon.
5.) Find the name of a regular polygon whose external angles are each 40 degrees.
6.) How many sides are in a polygon with angles adding up to 2065o?
Jan 30­11:23 AM
Jan 30­11:23 AM
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7.1 ­ Each angle.notebook
January 31, 2017
Exit slip: What is the measure of each internal and external angle in a regular decagon? What is the significance of these two numbers?
Jan 30­11:34 AM
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