exterior angles of polygons:. exterior angles:

Exterior Angles of Polygons:

Exterior Angles of Polygons:

Exterior Angles of Polygons:

• Exterior Angles:

Exterior Angles of Polygons:

• Exterior Angles:– Angles formed by a side of a polygon and the

extension of an adjacent side.

Exterior Angles of Polygons:

• Exterior Angles:– Angles formed by a side of a polygon and the

extension of an adjacent side.

Draw the figure and all it’s exterior angles:

Draw the figure and all it’s exterior angles:

Draw the figure and all it’s exterior angles:

How does the number of exterior angles compare to the sides of the

polygon?

How does the number of exterior angles compare to the sides of the

polygon?• It is always the same.

Formula to find the sum of the measures of the exterior angles of a

polygon:• All the angles add up to 360

Formula to find the sum of the measures of the interior angles of a

polygon:

Formula to find the sum of the measures of the interior angles of a

polygon:N is the number of sides.

Formula to find the sum of the measures of the interior angles of a

polygon:N is the number of sides.The sum of the interior angles is found by:S = (N-2)180

Formula to find the sum of the measures of the interior angles of a

polygon:N is the number of sides.The sum of the interior angles is found by:S = (N-2)180The measure of each interior angle is:S = (N-2)180

N

Remember that a regular polygon has all equal sides and angles.

Remember that a regular polygon has all equal sides and angles.

• You can find the measure of ONE EXTERIOR ANGLE of a regular polygon by:

• M = 360 N

Remember that a regular polygon has all equal sides and angles.

• You can find the measure of ONE EXTERIOR ANGLE of a regular polygon by:

• M = 360

• Where M is the measure of the exterior angle and N is the number of sides.

N

Find the measure of the exterior angles for the regular polygons:

Find the value of X.

12881

120108

134

x

Find the value of X.

• First find what the sum off all the angles must be.

12881

120108

134

x

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides.

12881

120108

134

x

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides.

12881

120108

134

x

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides. Put this information into the equation.

12881

120108

134

x

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides. Put this information into the equation.

12881

120108

134

x

S = (N-2)180

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides. Put this information into the equation.

12881

120108

134

x

S = (N-2)180

S = (6-2)180

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides. Put this information into the equation.

12881

120108

134

x

S = (N-2)180

S = (6-2)180

S = (4)180

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides. Put this information into the equation.

12881

120108

134

x

S = (N-2)180

S = (6-2)180

S = (4)180

S = 720

Find the value of X.

• First find what the sum off all the angles must be.

• The figure has 6 sides. Put this information into the equation.

12881

120108

134

x

S = (N-2)180

S = (6-2)180

S = (4)180

S = 720

720 = 108+134+128+81+120+x

Find the value of X

(2x + 1)

(3x + 8)

(x + 21)

• Given a regular octagon, find the following:

Sum of the interior angles:Sum = _______________

Sum of the exterior angles:Sum = _______________

Measure of each interior angle:Measure = _______________

Measure of each exterior angle: Measure = _______________

The measure of an exterior angle of a regular polygon is 30. Find the number of sides.

The measure of an interior angle of a regular polygon is 144. Find the number of sides.

Assignment:

• Handout. Due Wednesday.