interior angle of a regular 18-gon.
It is easier to calculate the exterior angle of a regular polygon of n-sides (n-gon) by the relation
exterior angle = 360/n
For a 18-gon, n=18, so exterior angle = 360/18=20 °
The value of each interior angle is therefore the supplement, or
Interior angle = 180-20=160 degrees.
Naming of a 9-gon
A polygon with 9 vertices is called a nonagon (in English) or enneagon (French ennéagone, but the English version is sometimes used)
You had a good start with the correct answer.
Exterior angle of a 15-gon
The exterior angle of a 15-gon can be calculated using the relation given in the first paragraph, namely
Exterior angle = 360/15=24 degrees
The formula of a volume of a cube:

We have 
Substitute:
![a^3=474.552\to a=\sqrt[3]{474.552}\\\\a=7.8\ m](https://tex.z-dn.net/?f=a%5E3%3D474.552%5Cto%20a%3D%5Csqrt%5B3%5D%7B474.552%7D%5C%5C%5C%5Ca%3D7.8%5C%20m)
Answer: The length of each side of the box is equal 7.8 m.
Answer:
option 4
Step-by-step explanation:


Answer:
(-5, 6) is not a solution.
Step-by-step explanation:
6=2(-5)+4
6=-10+4
-10+4=-6, not 6.