What are the similarities of a triangle and pyramid?

Both a triangle and a pyramid have three sides and three vertices in their simplest forms. A triangle, as a two-dimensional shape, consists of three straight sides and angles, while a pyramid is a three-dimensional shape that has a triangular base and triangular faces that meet at a single apex. Additionally, both shapes can be categorized based on their angles and sides—triangles can be classified as acute, obtuse, or right, and pyramids can be regular or irregular based on their base shapes. Both structures also exhibit geometric properties such as perimeter and area for triangles, and surface area and volume for pyramids.