The book was likely finished sometime in late 1987 or early 1988]. II.The collapse of Communism in the Balkans. It is likely that Gorbachevâs ideas for liberalizing East European communist states worked out best in the Balkan states of Bulgaria and Romania.
A polygon is a  closed plane figure made of three or more straight line segments. The term originated from ancient Greek polygonon, which breaks down to polus (many) and gonia (angle). A polygon is a closed plane figure made of three or more straight line segments.
A polygon can have four sides and four angles, or many sides and many angles. A three-sided polygon is called a triangle, from the Greek word tri meaning three as in tricycle, or tripod. A three-sided polygon is called a triangle, from the Greek word tri meaning three as in tricycle, or tripod. It is very easy to find examples of triangles in the world around us, as in this street sign: A geometric drawing of a triangle is seen below. Every polygon is formed of points and segments joining the points. Each point is called a vertex (the plural for vertex is vertices), and the segments are called the sides of the polygon. The triangle below is called triangle ABC using the triangle symbol in the name, as shown. The triangle is the simplest polygon, and one of the most useful geometric figures. The triangle is also the strongest geometric figure, and is therefore used in the construction of buildings and bridges. Take a drinking straw, and cut it into three pieces.