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A polygon of n sides has a half its interior angles equals to 150 degrees.while the rest of are equal to 170 degrees each.
Find the number of sides of the polygon
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18-gon.
18 sides and 18 vertices.
9 angles by 150° and 9 angles by 170°.
9*150° + 9*170° = 2880°.
From the other side, (18-2)*180° = 2880°.