A 12-sided two-dimensional polygon is called a dodecagon. A regular dodecagon has 12 sides that are all the exact same length and internal angles that are 150 degrees each. Since there are 12 internal angles, the total internal angles add up to 1,800 degrees.
Know MoreA polygon refers to any two-dimensional shape that consists of only straight edges and has a closed shape. The most common polygons are those with a small amount of sides, such as triangles with three sides and squares with four sides. A dodecagon has 12 straight edges in a closed loop along with 12 vertices where the edges meet.
Learn more about ShapesA polygon with seven sides is called a heptagon. A polygon is a closed geometric shape that has at least three sides and angles.
Full Answer >A nine-sided polygon is called a nonagon. The prefix "non" is derived from the Latin "nonus," which means "ninth" to allude to the nine sides and angles of the polygon.
Full Answer >A 20-sided polygon is called an icosagon. Along with having 20 sides, all icosagons have 20 interior angles that add up to a total of 3240 degrees.
Full Answer >An 8-sided polygon is called an octagon. One common use of the octagon is in the iconic red stop sign that's used throughout the United States.
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