Scientists tested crows on their ability to recognize “geometric regularity,” a skill previously assumed to be unique to ...

but sometimes they are greater than or less than a right angle. A 2D shape could have line symmetry or rotation symmetry, or both! 3D shapes are described by their faces, edges and vertices.

Polygons are multi-sided shapes with different properties ... Circle theorems - Higher - Edexcel Circles have different angle properties described by different circle theorems.