How does polygon looks like

We explain how polygons are taught in primary school, with examples of regular and irregular versions of each multi-sided shape. Login or Register to add to your saved resources. A polygon is a flat, two-dimensional 2D shape with straight sides that is fully closed all the sides are joined up. The sides must be straight.

Polygons may have any number of sides. A polygon A shape with curved sides is not a polygon. A shape that is not fully closed is not a polygon. Regular and irregular polygons A regular polygon is a polygon in which all sides are of all the same length and at the same angles. Although they still must be straight and joined up. It is called a square. When and how polygons are taught in primary school What is taught How it might be taught Year 1 Children are taught to name common 2D shapes including polygons such as squares, rectangles, triangles, pentagons, hexagons and octagons.

Children may learn the shapes through matching activities, going on a shape walk in the school grounds, flash-cards and games. All rights reserved. Australian Business Number 53 If you experience difficulties when using this Website, tell us through the feedback form or by phoning the contact telephone number.

A polygon is a closed plane figure with three or more sides that are all straight. Some examples of polygons are shown below. A triangle with only acute internal angles is called an acute or acute-angled triangle. One with one obtuse angle and two acute angles is called obtuse obtuse-angled , and one with a right angle is known as right-angled.

Each of these will also be either equilateral, isosceles or scalene. Four-sided polygons are usually referred to as quadrilaterals, quadrangles or sometimes tetragons. In geometry the term quadrilateral is commonly used. The term tetragon is consistent with polygon, pentagon etc. You may come across it occasionally, but it is not commonly used in practice.

Parallelogram : Opposite sides are parallel, opposite sides are equal in length, opposite angles are equal. Rhombus : A special type of parallelogram in which all four sides are the same length, like a square that has been squashed sideways.

Trapezium or trapezoid : Two sides are parallel, but the other two sides are not. Side lengths and angles are not equal. Isosceles Trapezium or trapezoid : Two sides are parallel and base angles are equal, meaning that non-parallel sides are also equal in length. Kite : Two pairs of adjacent sides are of equal length; the shape has an axis of symmetry. Irregular Quadrilateral : a four-sided shape where no sides are equal in length and no internal angles are the same.

A six-sided shape is a hexagon, a seven-sided shape a heptagon, while an octagon has eight sides…. The names of polygons are derived from the prefixes of ancient Greek numbers. The Greek numerical prefix occurs in many names of everyday objects and concepts. In geometry, you could have a four-sided polygon that points outward in all directions, like a kite , or you could have the same four sides so two of them point inward, forming a dart.

The kite is convex; the dart is concave. Think of a bowtie-shaped simple hexagon 6 sides. Simple polygons have no self-intersecting sides. Complex polygons , also called self-intersecting polygons, have sides that cross over each other. The classic star is a complex polygon. Most people can doodle a star on paper quickly, but few people label it a pentagram , complex polygon, or self-intersecting polygon. You cannot draw a complex triangle. For every polygon with four or more sides, a complex polygon can be drawn.

A complex quadrilateral is that familiar bowtie shape, but it is considered to have only four sides, because one pair of opposite sides has twisted to cross each other. Just as you do not count the crossed sides as four line segments, you do not count the two angles they create as interior angles.

The complex quadrilateral still only has four sides and four interior angles. Complex polygons may be hard to imagine unless you think of them with elastic sides.

If you could lift part of the polygon up and twist it, so two sides cross one another, and then put it down flat again, you would have a complex polygon. Because you twisted two sides, you still have those two sides they do not double in number by crossing. They also do not create new vertices where they cross.