Assertion: polygon's angle | /r/HasProperty | right
Facets:
Source sentences:
text: If edges are equal, or angles are right, the symmetry of the lattice is higher.
text: Thales' theorem implies that if the circumcenter is located on a side of the triangle, then the opposite angle is a right one.
text: The opposite side is sometimes longer when the corresponding angles are acute, but it is always longer when the corresponding angles are right or obtuse.