
RE: PARCC Definition of Trapezoid
Posted:
May 1, 2013 12:47 PM


I think it's valuable that you saw this. I hope others will become aware as well. The definition you saw in the 2005 glossary is an old one, and New York State has stayed with it at least up until that time.
However, many states and countries and publishers have been using the new definition (at least two parallel sides) for a long time. The newer definition is more consistent with other mathematical definitions like that of isosceles triangleat least two congruent sides. Then an equilateral triangle is also isosceles. Similarly, with the newer definition of trapezoid, every parallelogram is also a trapezoid.
Elliott Bird Consultant in Mathematics Education Professor of Mathematics, Emeritus L.I.U. ________________________________________ From: ownernyshsmath@mathforum.org [ownernyshsmath@mathforum.org] on behalf of Holly Thomas [hollythomas@mail.ircsd.org] Sent: Wednesday, May 01, 2013 12:05 PM To: nyshsmath@mathforum.org Subject: PARCC Definition of Trapezoid
I've been reviewing recently released PARCC documents and was confused that PARCC is defining a trapezoid as having "at least one pair of parallel sides". However, the most recent definition I can find issued by NYS is in the 2005 Standards math glossary, in which a trapezoid is defined as having exactly one pair of parallel sides. Since this will impact instruction from Grade 3 on, I'm curious is anyone else is aware of this issue, or any discussions surrounding it.
Holly Thomas Math Coach Indian River Central School District Philadelphia, NY ******************************************************************* * To unsubscribe from this mailing list, email the message * "unsubscribe nyshsmath" to majordomo@mathforum.org * * Read prior posts and download attachments from the web archives at * http://mathforum.org/kb/forum.jspa?forumID=671 ******************************************************************* ******************************************************************* * To unsubscribe from this mailing list, email the message * "unsubscribe nyshsmath" to majordomo@mathforum.org * * Read prior posts and download attachments from the web archives at * http://mathforum.org/kb/forum.jspa?forumID=671 *******************************************************************

