6.2 Lesson

Take out your homework

Find the value of x.

73o

38o

x

y

z

Find the value of y.

73o

38o

x

y

z

Find the value of z.

73o

38o

x

y

z

These are called exterior angles of a triangle. What is the sum of the

exterior angles?

73o

38o

x

y

z

These are called exterior angles of a triangle. What is the sum of the

exterior angles?

73o

38o

x

y

z

Find the value of a.

32O

114O

a

b

c

d

Find the value of a.

32O

114O

a

b

c

d

Find the value of b.

32O

114O

a

b

c

d

Find the value of c.

32O

114O

a

b

c

d

Find the value of d.

32O

114O

a

b

c

d

What is the sum of a quadrilateral’s exterior angles?

32O

114O

a

b

c

d

Generalize

• What do you think will be the sum of interior angles of a – Pentagon?– Hexagon?– Octagon?– N-gon?

Conjectures

• C-40 The sum of the measures of one set of exterior angles is _________________.

What is the measure of each exterior angle below?

What is the measure of each interior angle below?

What are two methods for finding the measure of one interior angle in

a regular polygon?

Conjectures

C-41 The measure of each angle of an equiangular n-gon can be found by using either of the following expression:

_________________________ or

_________________________

Find the measure of one interior angle of a regular decagon.

Find the measure of each interior angle of following figure.

Homework6.2

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