I think the awkward science is quite amusing to me
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:
4√34
Step-by-step explanation:
Let the unknown side be y
y^2 = 20^2 + 12^2
y^2 = 400 + 144
y^2 = 544
Take the square root of both side
y = √544
y = √(16x34)
y = √16 x √34
y = 4√34
Answer:
693.6
Step-by-step explanation:
A and T are points. On their own, they cannot define a line. So we can rule out choice A
WCR and TRA are angles. For any triple the points do not fall on the same straight line. So we cannot define any lines here. This crosses off choice B
Choice C is the answer because WC does define a line. We only need two points to form a line. Similarly CR does the same job. We draw a line marker with two arrows at each end to be placed over the letters to indicate "line".
Choice D is similar to choice D; however, it is not the answer because WT is the same line as WC. In other words, WC = WT. We haven't named a new line at all. We're simply repeating ourselves.