The perimeter is the sum of all three sides of the triangle. In this case it is 18.
Explanation:
In geometry, a triangular crystal is a three-sided crystal; it is a polyhedron made of a triangular base, a deciphered duplicate, and 3 faces joining comparing sides. A privilege triangular crystal has rectangular sides, else it is angled.
A triangular prism has two triangular bases and three rectangular sides and is a pentahedron since it has five countenances. Outdoors tents, triangular rooftops and "Toblerone" wrappers - chocolate pieces of candy - are instances of triangular prisms.
