About: http://webisa.webdatacommons.org/136795059

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Manipulative Activity: An object has line symmetry if, when you draw a line down the middle, the left side is a mirror image of the right side.
http://www.w3.org/ns/prov#wasQuotedFrom	mathforum.org