Answer: combining like terms
Step-by-step explanation:
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
Answer:

Step-by-step explanation:



Answer: These Lines are <em>Parallel</em>
Step-by-step explanation: For two lines to be parallel, they must have the same slope with different y-intercepts. Both of the lines above have a slope of 3 and differing y-intercepts of 4 and -5. Therefore, these lines must be parallel to one another.