id: 06451940
dt: a
an: 2015d.00633
au: Jones, Keith; Fujita, Taro
ti: Characterising triangle congruency in lower secondary school: the case of
Japan.
so: Ubuz, Behiye (ed.) et al., CERME 8. Proceedings of the eigth congress of
the European Society of Research in Mathematics Education, Antalya,
Turkey, February 6‒10, 2013. Ankara: Middle East Technical University
(ISBN 978-975-429-315-9). 655-664 (2013).
py: 2013
pu: Ankara: Middle East Technical University
la: EN
cc: G43
ut: triangles; geometry; congruency; textbooks; secondary school
ci:
li:
ab: Summary: Congruence, and triangle congruence in particular, is generally
taken to be a key topic in school geometry. This is because the three
conditions of congruent triangles can be used when proving geometrical
theorems and also because triangle congruency relates to the idea of
mathematical similarity via similar triangles. Despite the role of
congruency, and of congruent triangles in particular, there appears to
be limited research on the topic. In this paper we report on the
approach to triangle congruency in textbooks used in lower secondary
school in Japan specifically in grade 8 (students aged 13‒14). We
found that the modicum of practical tasks entailed various conceptions
(measuring, transformations, etc.) whereas the proof problems which
predominated expected students to utilise corresponding parts and known
facts.
rv: