All of the centra angles in a regular polygon must add up to 360 degrees. Also, because you're told that it is a regular polygon, the "regular" indicates that all of the central angles will be the same. Divide 360 degrees by 18 degrees to get the number of central angles, which is the same as the number of sides. 360/18 = 20. Therefore, the polygon has 20 sides. Hope that helps!
Answer:
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Step-by-step explanation:
<u>Step 1: Set the second equation into the first
</u>




<u>Step 2: Solve the second equation
</u>
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
Answer: 
The answer is 30 because you have to multiply the two together
Answer:
<h3><em>
40,08791209</em></h3>
Step-by-step explanation: