It is the intersection of two planes or the line joining two vertices.
a cube
A tetrahedron.
Triangular pyramid
vertex
There is no 3 dimensional figure with JUST 3 edges.
A closed three-dimensional figure formed by four or more polygons that intersect only at their edges is called a polyhedron. It contains flat faces, straight edges, and sharp corners or vertices.
The edges form the two dimensional pattern of a three dimensional figure.A pattern, also known as a netanswer 2: An orthographic projection
A cube
It is a cube.
A triangular prism.
A quadrilateral based pyramid (the base has four sides).
a polygon(or polyhedron) is a three dimensional figure that has straight edges. * * * * * A polygon is 2 dimensional, a polyhedron is 3-d.