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An apothem of a regular polygon is a segment from its center to the midpoint of a side. You can use the apothem to find the area of a regular polygon using this formula: A = pa/2 where p is the perimeter of the figure and a is the apothem. For a regular octagon with side length 11, the perimeter p = 8(11) = 88. So the area would be A = 88(8.85)/2 = 389.4 square units.
m3 is not defined.
Exterior angles of ANY polygon add to 360 degrees. Individual angles are therefore 360/n where n is the number if sides. 72
The interior angle is the angle formed from two sides of a nth-sided polygon. Because the polygon is regular, all angles formed from any two sides of the polygon are equal. It can be proven, but I won't attempt to, that to find the amount of sides, you use 180-[interior angle], and divide the answer by 360. In this case, 180-156=24, 360/24= 15, thus the polygon has 15 sides. One way to prove it is to imagine the polygon and divide it into isosceles triangles. But I won't go there.
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This figure is a regular 12-sided polygon. Find m<4
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This figure is a regular 12-sided polygon. Find m<4
360/exterior angle = number of sides of a regular polygon
The polygon is a Quadrilateral.
I assume you mean a polygon inscribed in a circle. It is regular if all its sides and angles are equal.