Answer:
There is something called "criteria of congruence for triangles".
Those criteria say that, with some data of the triangles, we can know if the triangles are equivalent.
For example one of the criteria is SSS.
Side-side-side.
This means that all the triangles with equal side length for all their sides are equivalent.
So if the information that we give to the factory is the side length of the 3 sides of the triangle, the triangle will be well defined.
Following those criteria, the other 2 options can be:
SAS
Side-Angle-Side
(so you can give the length of two sides and the angle between them)
ASA
Angle-Side-Angle.
(You can give the value of two angles and the length of the side between those two angles)