Concave polygon does not contain all other vertices in its edges and interior. The convex hull of the concave polygon's vertices, and that of its edges, contains points that are exterior to the polygon. Concave polygon A simple polygon that is not convex is called concave, non-convex or reentrant. A concave polygon will always have at least one reflex interior angle—that is, an angle with a measure that is between 180 degrees and 360 degrees exclusive. Some lines containing interior points of a concave polygon intersect its boundary at more than two points. Some diagonals of a concave polygon lie partly or
38 Degrees comes from the speed with which 38 Degrees can launch a campaign or find out members' views. Campaigning techniques include both online methods, such as mass email, social media, blogs and online petitions, and offline methods, such as calling an MP or visiting a surgery. 38 Degrees has also fundraised from its membership to commission legal advice and to run advertising campaigns. 38 Degrees 38 Degrees is a British not-for-profit political-activism organisation. It describes itself as "progressive" and claims to "campaign for fairness, defend rights, promote peace, preserve the planet and deepen democracy in the UK". In October 2013, it