X sides polygon12/11/2023 ![]() ![]() These can sometimes be useful in helping you remember how many sides a polygon has. The Greek numerical prefix occurs in many names of everyday objects and concepts. The names of polygons are derived from the prefixes of ancient Greek numbers. 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.Įach of these will also be either equilateral, isosceles or scalene. The internal angles of a triangle always add up to 180°.Ī triangle with only acute internal angles is called an acute (or acute-angled) triangle. Triangles can also be described in terms of their internal angles (see our page on Angles for more about naming angles). Scalene – all three sides, and all three internal angles, are different.Isosceles – has two equal sides, with the third one a different length.Equilateral – all the sides are equal lengths, and all the internal angles are 60°.There are several different types of triangle (see diagram), including: Three-Sided Polygons: TrianglesĪ three-sided polygon is a triangle. Polygons are usually defined by the number of sides that they have. The angles between the sides of the shape.So all other quadrilaterals are irregular.When working with polygons the main properties which are important are: The only regular (all sides equal and all angles equal) quadrilateral is a square. and that's it for the special quadrilaterals. one of the diagonals bisects (cuts equally in half) the other. ![]() ![]() the diagonals, shown as dashed lines above, meet at.The KiteĮach pair is made of two equal-length sides that join up. (the US and UK definitions are swapped over!)Īn Isosceles trapezoid, as shown above, has left and right sides of equal length that join to the base at equal angles. NOTE: Squares, Rectangles and Rhombuses are allĪ trapezoid (called a trapezium in the UK) has a pair of opposite sides parallel.Īnd a trapezium (called a trapezoid in the UK) is a quadrilateral with NO parallel sides: Also opposite anglesĪre equal (angles "A" are the same, and angles "B" The ParallelogramĪ parallelogram has opposite sides parallel and equal in length. In other words they "bisect" (cut in half) each other at right angles.Ī rhombus is sometimes called a rhomb or a diamond. The RhombusĪ rhombus is a four-sided shape where all sides have equal length (marked "s").Īlso opposite sides are parallel and opposite angles are equal.Īnother interesting thing is that the diagonals (dashed lines) meet in the middle at a right angle. The SquareĪ square has equal sides (marked "s") and every angle is a right angle (90°)Ī square also fits the definition of a rectangle (all angles are 90°), and a rhombus (all sides are equal length). The little squares in each corner mean "right angle"Ī rectangle is a four-sided shape where every angle is a right angle (90°).Īlso opposite sides are parallel and of equal length. Let us look at each type in turn: The Rectangle Some types are also included in the definition of other types! For example a square, rhombus and rectangle are also parallelograms. There are special types of quadrilateral: They should add to 360° Types of Quadrilaterals Try drawing a quadrilateral, and measure the angles. interior angles that add to 360 degrees:.(Also see this on Interactive Quadrilaterals) Properties ![]()
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |