How many {has facet polytope} are to/by {rectangle} ?
How many of the facet polytope rectangle are there?
How many have the facet polytope {rectangle} ?
SELECT ( COUNT ( ?o ) AS ?s ) { ?o property:has_facet_polytope resource:rectangle }
SELECT (COUNT(?sub) AS ?subs ) {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?sub .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P1312> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> http://wikidata.dbpedia.org/resource/Q209 .
} 

SELECT (COUNT(?sub) AS ?value ) { ?sub wdt:P1312 wd:Q209 }
5