Assertion: octahedron's triangle | /r/CapableOf | converge at each vertex
Facets:
Source sentences:
text: Tetrahedrons have 3 triangles converging at each vertex and a total of 4 triangular facets (see 1 st image on right)
text: Octahedrons have 4 triangles converging at each vertex and a total of 8 triangular facets (see 2nd image on right)