Assertion: parallelogram's pair | /r/HasProperty | supplementary
Facets:
value: always
type: DEGREE
Source sentences:
text: Theorem 48: If all pairs of consecutive angles of a quadrilateral are supplementary, then it is a parallelogram.
text: If you start at any angle, and go around the parallelogram in either direction, each pair of angles you encounter always are supplementary - they add to 180°.