A 3D shape with all straight edges and flat faces ... A square-based pyramid has eight edges, 4 × 2 = 8 \(F\) is the number of faces. A cuboid has six faces. \(V\) is the number of vertices.

Vertices - A vertex is a corner where edges meet (the plural is vertices). For example a cube has 8 vertices. 2D shapes are boring. Ah! Not really. But got your attention. Now. 3D shapes ...