What is the measure of each angle in a regular decagon

1) What is the measure of each angle in a regular decagon?
Select one:
A. 135
B. 144
C. 147
D. 150


2) Troy is building a model sailboat to scale. The actual boat sail measures as follows:

measures are 28,36,20

Which set of model sail side lengths would be proportional to the actual sail?

Select one:
A. Not enough information
B. 10 in, 12 in, 14 in
C. 5 in, 14 in, 18 in
D. 5 in, 7 in, 9 in




3) The cross products shown would be used to solve which proportion?

71(42) = 13a

Select one:
A. 13/a = 71/42
B. 13/42=71/a
C. 42/71=13/a
D. a/71=13/42


4) Match each proportion in the left column with its solution in the right column

1) d/4=54/24 - 9
2) 54/6=45/d - 3
3) 2/6 =d/9 - 5
4) 24/d=84/7 - 2

1) 8*18 = 144
Answer B

2) D. 5 in, 7 in, 9 in

3) D. a/71=13/42

What is the measure of each angle in a regular decagon?

Sum of the interior angles of a regular convex n-gon is:

Σ = (n - 2) * 180

for a decagon...10 sides...

Σ = 8 * 180 = 1440
therefore, each angle is 144º

one at a time

MAD