Читать книгу Geometry for Students and Parents - Sergey D Skudaev - Страница 5

Polygons are two-dimensional figures made of a variable number of segments. For example, polygons made of 3 line segments are called triangles. Polygons made of 4 line segments are called quadrilaterals. Polygons made of five line segments are called pentagons. Polygons made of six line segments are called hexagons. If all the sides of the polygon are equal, the polygon is called a regular polygon: equilateral triangle, regular quadrilateral, regular pentagon and a regular hexagon. See figure 9.

Figure 9. Regular polygons.