A pair of triangles can form a 4 sided quadrilateral
They are congruent triangles.
Trignometry
trapezoid
Some triangles are equilateral, but not all of them. There are three types of triangles. Triangles which have three equal sides and three equal angles are called equilateral triangles. Isosceles triangles have two equal sides and two equal angles. Scalene triangles have no equal sides and no equal angles.
Some, but not all. Triangles with 2 congruent sides are called isoceles triangles. Triangles with 3 congruent sides are called equilateral triangles.
Similar triangles
The set of all triangles, probably.
A pair of triangles can form a 4 sided quadrilateral
They are congruent triangles.
hexagon
Trignometry
trapezoid
There is no word for the fear of boogers
what is the fear of dusbins called ?
Those would be SIMILAR triangles.
The fear of fears is called phobophobia. It is the fear of getting a phobia.