Assertion: regular polygon's angle | /r/HasProperty | right angles
Facets:
value: by definition
type: OTHER
value: for both
type: PURPOSE
Source sentences:
text: A square is also a special quadrilateral because all four sides are congruent and all four angles are right angles.
text: All four angles are right angles for both.
text: By definition, all the interior angles of a square are right angles -- That means that they are all 90 degrees.