# 2-Dimensional Shapes – Name – Definitions and Properties

** 2D Shapes – Names and Properties**

**Definition and Properties**

**2-dimensional shapes have 2 dimensions length and width. **

**Rectangle**

A rectangle is a 2-dimensional 4 sided polygon.

A rectangle have 4 sides, 4 angles and 4 vertices. The total of 4 angles is 360 degree.

**Square**

A square is a 2-dimensional 4 sided polygon.

A square have 4 sides, 4 angles and 4 vertices.

The total of 4 angles is 360 degree.

**Circle**

A circle is a closed 2-dimensional figure.

A circle is a collection of all the points in a plane, whose all points are same distance from a fix point. The fixed point is called the centre of the circle, and the distance between centre and any point on the circle is called the radius of the circle.

**Triangle**

A triangle is a 2-dimensional 3 sided polygon.

A triangle have 3 sides, 3 angles and 3 vertices.

The total of 3 angles is 180 degree.

**Right Triangle**

A right triangle is a 2-dimensional 3 sided polygon.

A right triangle have 3 sides, 3 angles and 3 vertices. One angle of right triangle is right angle or 90 degree and the total of 3 angles is 180 degree.

**Parallelogram**

A parallelogram is a 2-dimensional 4 sided polygon.

A parallelogram have 4 sides, 4 angles and 4 vertices.

The total of 4 angles is 360 degree.

Opposite side of a parallelogram is equal and parallel.

Opposite angles of a parallelogram is equal.

**Trapezium**

A trapezium is a flat closed figure in which one pair of opposite sides are parallel. The total of all interior angles are 360 degree.

**Rhombus**

A rhombus is a quadrilateral (closed shape, plane figure) with four straight sides that are equal length also opposite sides are parallel. Opposite interior angles of a rhombus are equal.

**Pentagon**

A pentagon is a geometrical shape(polygon) has 5 sides, 5 vertices and 5 angles.

The sum of all interior angles of a pentagon is 540 degree.

**Oval**

An oval is a closed curve in a plane looks like an eg or ellipse. An oval has no straight sides and no corners. An oval has one face.

**Hexagon**

A hexagon is a geometrical shape(polygon) has 6 sides, 6 vertices and 6 angles. The sum of all interior angles of a hexagon is 720 degree.

**Heptagon**

A heptagon is polygon(closed shape with 7 straight sides).

A heptagon has seven straight sides, 7 angles and 7 corners i.e. vertices.

A heptagon is known as septagon.

The sum of all interior angles of a heptagon is 900 degree.

**Octagon**

** **An octagon is a geometrical closed figure which is made by eight straight lines. An octagon has eight straight sides, 8 angles and 8 corners i.e. vertices. The sum of all interior angles of a octagon is 1080 degree.

**Decagon**

A decagon is a geometrical closed figure which is made by ten straight lines.

A decagon has ten straight sides, ten angles and ten corners i.e. vertices. The sum of all interior angles of a decagon is 1440 degree.

**Dodecagon**

As the name says, the twelve sided polygon is known as dodecagon.

A dodecagon is a geometrical closed figure which is made by twelve straight lines. A dodecagon has twelve straight sides, twelve angles and twelve corners i.e. vertices. The sum of all interior angles of a dodecagon is 1800 degree.