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2-dimensional shapes - OCR2-dimensional shapes

2-dimensional shapes are flat. The perimeter of a 2D shape is the total distance around the outside of the shape. The area of a 2D shape is the space inside the shape.

Part of MathsGeometry and measure

2-dimensional shapes

2-dimensional (2D) shapes have only two dimensions, and .

A polygon is a closed 2D shape with straight sides. Polygons are named depending on the number of sides:

  • Triangle (3 sides)
  • Quadrilateral (4 sides)
  • Pentagon (5 sides)
  • Hexagon (6 sides)
  • Octagon (8 sides)
Triangle; Quadrilateral; Pentagon; Hexagon; Octagon

A regular polygon has sides that are equal in length and equal angles. A regular triangle is called an equilateral triangle. A regular quadrilateral is called a square.

Equilateral triangle; Square; Regular pentagon; Regular hexagon; Regular octagon