Geometry

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Geometry is a kind of mathematics that studies the size, shapes, positions and dimensions of things. We can only see or draw shapes that are flat (2D) or solid (3D), but mathematicians (people who study math) are able to study shapes that are 4D, 5D, 6D, and so on.. Squares, circles and triangles are some of the simplest shapes in flat geometry. Cubes, cylinders, cones and spheres are simple shapes in solid geometry.

Uses[change | change source]

Plane geometry can be used to measure the area and perimeter of a flat shape. Solid geometry can also measure a solid shape's volume and surface area.

Geometry can be used to calculate the size and shape of many things. For example, geometry can help people find:

Origins[change | change source]

Geometry is one of the oldest branches of mathematics. Geometry began as the art of measuring the shape of land so that it could be shared fairly between people. The word "geometry" means "to measure the land". It has grown from this to become one of the most important parts of mathematics. The Greek mathematician Euclid wrote the first book about geometry, a book called The Elements.

Non-euclidian Geometry[change | change source]

Plane and solid geometry are called "Euclidian Geometry", because Euclid helped create it. Many years later, some mathematicians tried to create new tkinds of Geometriy that did not follow the rules of Euclidian Geometry, so they were called "non-euclidian" (not created by Euclid).

Non-euclidian geometry can be much more complicated than euclidian geometry, but it can be used to make GPS devices, for example.

Examples[change | change source]

Geometry starts with a few simple ideas that are thought to be true, called axioms. Such as:

  • A straight line is the shortest distance between two points. For example, Sophie pulls a piece of string from one point to another point. A straight line between the two points will follow the path of the tight string.
  • A plane is a flat surface that does not stop in any direction. For example imagine a wall that extends in all directions infinitely.

Related pages[change | change source]