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the size of an interior angle of a regular polygon is 3x. It's exterior is (x- 20)°. Find number if the sides of the polygon.​

User SSA
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2 Answers

4 votes

Answer:

Explanation:

Since the angles are supplements, 3x + x - 20 = 180. Solving this, we find that x = 50, and 3x = 150. Since dodecagons have interior angles of 150 degrees, the answer is 12 sides.

User Ftl
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1 vote

Answer: 12

Step-by-step explanation: Since the angles are supplements, 3x + x - 20 = 180. Solving this, we find that x = 50, and 3x = 150. Since dodecagons have interior angles of 150 degrees, the answer is 12 sides.

User GazB
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