Assertion: tetrahedron's triangle | /r/HasProperty | congruent
Facets:
value: in a tetrahedron
type: LOCATION
value: to one another
type: TRANSITIVE-OBJECT
value: clearly
type: DEGREE
Source sentences:
text: Since each vertex is thus effectively formed by three different internal angles from triangles that are congruent, and since the three internal angles of a triangle always add up to one hundred and eighty degrees (180°), then the face angles at each vertex of an isosceles tetrahedron must also sum to one hundred and eighty degrees.
text: A regular tetrahedron is bounded by four congruent equilateral triangles.
text: Clearly, these equilateral triangles are congruent to one another.
text: In a tetrahedron all the triangles have to be congruent.
text: Regular tetrahedra, in which all edges have equal length and all faces are congruent equilateral triangles, are one of the five types of Platonic solids.