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Re: Geometry Proof Question
Posted:
Sep 13, 2012 5:25 PM


I have told my students the following about the using theorems in the justifications in proofs:
You may refer to a theorem by its name. You may quote the entire theorem. You may paraphrase the theorem. You may use a combination of symbols and words to describe the theorem, as long as the meaning is clear and correct. You may not rely on the number that the text book gives the theorem. It is meaningless to someone with a different book.
In general, I also tell them that the harder the teacher has to work in understanding their answers, the more likely that something will be missed or will not be accepted.
We emphasize twocolumn proofs during the year, and I explain to my students why we do that, but I have also told them that paragraph and flow proofs are acceptable on the regents.
I think that the examples given are not a good idea for teaching during the year, and in a couple of places are straight out incorrect: congruent and equal are not exactly the same concept, and corresponding does not mean the same thing as either of them.
There's one theorem that my class refers to as the cross country skis theorem, because that's how I teach it. But I don't think I can expect other teachers to recognize what they mean if they were to write that in a proof.
Evelyne Stalzer

On Thu, Sep 13, 2012 at 3:24 PM, Leslie Tanner <latanner@yorkcsd.org> wrote: > I was also concerned because I use flow chart proofs and some students > really love using them. What if a teacher does not accept this method of > proof? > > Leslie Tanner > York Central School > >>>> Kevin Connolly <KCONNOLLY@elmiracityschools.com> 09/13/12 2:48 PM >>> > proctor > > ________________________________ > From: ownernyshsmath@mathforum.org [ownernyshsmath@mathforum.org] On > Behalf Of TKENYON@crcs.wnyric.org [TKENYON@crcs.wnyric.org] > Sent: Thursday, September 13, 2012 2:01 PM > To: nyshsmath@mathforum.org > Subject: Re: Geometry Proof Question > > You may not proctor your own exams either. > > > > Tom Kenyon > CRCS Mathematics/Physics > tkenyon@crcs.wnyric.org<mailto:tkenyon@crcs.wnyric.org> > > ownernyshsmath@mathforum.org wrote:  > To: "nyshsmath@mathforum.org"<mailto:nyshsmath@mathforum.org> > <nyshsmath@mathforum.org><mailto:nyshsmath@mathforum.org> > From: Jenni Leaver > Sent by: ownernyshsmath@mathforum.org<mailto:ownernyshsmath@mathforum.org> > Date: 09/13/2012 12:17PM > Subject: Re: Geometry Proof Question > > And to piggyback on Tom's email, our principal has reminded us that we will > NOT be allowed to grade our own exams this year. > > Where do we stand on proctoring our own exams? > > Jenni > > From: "TKENYON@crcs.wnyric.org"<mailto:TKENYON@crcs.wnyric.org> > <TKENYON@crcs.wnyric.org><mailto:TKENYON@crcs.wnyric.org> > To: nyshsmath@mathforum.org<mailto:nyshsmath@mathforum.org> > Sent: Thursday, September 13, 2012 11:11 AM > Subject: Re: Geometry Proof Question > > I've seen the following styles as acceptable by teachers from various > schools: "Theorem 5.2" , "Definition of an angle bisector" , "The bisector > of an angle is a ray whose endpoint is at the vertex of the angle and which > divides the angle into two congruent angles" , "< bisector ÷ an < into 2 ~= > <'s" [~= being written as the correct symbol for congruent.] > > Our evaluations depend on how well the students do on the Regents exam. I > foresee a huge uproar if situations like this occur: teacher A's students > (graded by teacher X) get full credit for "def'n of an angle bisector", but > teacher B's students (graded by teacher Y) lose credit for "def'n of an > angle bisector." To the best of my knowledge, what is acceptable on the > Integrated Geometry Regents proofs has never been conveyed to teachers. Nor > have the rubrics ever addressed this. > > This seems to be a problem that needs to be addressed NOW, before students > spend the year learning how to write reasons which will be considered > unacceptable. Or, will we be told to accept anything that's even close? Or, > will they realize this is a huge problem and scrap giving proofs on the > Regents exam? > > > Tom Kenyon > CRCS Mathematics/Physics > tkenyon@crcs.wnyric.org<mailto:tkenyon@crcs.wnyric.org> > > ownernyshsmath@mathforum.org wrote:  > To: nyshsmath@mathforum.org<mailto:nyshsmath@mathforum.org> > From: Bob Thomas > Sent by: ownernyshsmath@mathforum.org<mailto:ownernyshsmath@mathforum.org> > Date: 09/13/2012 09:15AM > Subject: Geometry Proof Question > > While discussing the new curriculum and planning, we have a new teacher who > has some different ways of completing proofs. We are wondering if anyone has > seen them or would allow credit for it on the regents. > > For example, she writes: (= means congruent) > > //> = <'s > for "parallel lines cut but a transversal form two congruent alternate > interior angles" > > or > > = P = (triangle symbol) = > for "Corresponding parts of congruent triangles are congruent" > > A couple of us are uncomfortable with these type of "reasons" on a proof and > are curious, do you know if they would be given full credit and what your > thoughts are. Thank you for your time. > >  End of Forwarded Message > > ******************************************************************* > * To unsubscribe from this mailing list, email the message > * "unsubscribe nyshsmath" to > majordomo@mathforum.org<mailto:majordomo@mathforum.org> > * > * Read prior posts and download attachments from the web archives at > * http://mathforum.org/kb/forum.jspa?forumID=671 > ******************************************************************* > > >  > BEGINANTISPAMVOTINGLINKS >  > > Teach CanIt if this mail (ID 02HWBfqoN) is spam: > Spam: > http://milton1.wnyric.org/canit/b.php?i=02HWBfqoN&m=5478906ca402&t=20120913&c=s > Not spam: > http://milton1.wnyric.org/canit/b.php?i=02HWBfqoN&m=5478906ca402&t=20120913&c=n > Forget vote: > http://milton1.wnyric.org/canit/b.php?i=02HWBfqoN&m=5478906ca402&t=20120913&c=f >  > ENDANTISPAMVOTINGLINKS > > ******************************************************************* * To > unsubscribe from this mailing list, email the message * "unsubscribe > nyshsmath" to majordomo@mathforum.org<mailto:majordomo@mathforum.org> * * > Read prior posts and download attachments from the web archives at * > http://mathforum.org/kb/forum.jspa?forumIDg1 > ******************************************************************* > > > ________________________________ > > Spam<http://milton1.wnyric.org/canit/b.php?i=0lHWEhqPX&m=05531f801780&t=20120913&c=s> > Not > spam<http://milton1.wnyric.org/canit/b.php?i=0lHWEhqPX&m=05531f801780&t=20120913&c=n> > Forget previous > vote<http://milton1.wnyric.org/canit/b.php?i=0lHWEhqPX&m=05531f801780&t=20120913&c=f> > ******************************************************************* * 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?forumIDg1 > ******************************************************************* > ******************************************************************* > * 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 *******************************************************************



