For a craft project, two equilateral triangles are taped together to create a quadrilateral.

For a craft project, two equilateral triangles are taped together to create a rhombus quadrilateral. In Euclidean geometry, a rhombus is a simple quadrilateral whose four sides all have the same length. Another name is equilateral quadrilateral, since equilateral means that all of its sides are equal in length.