Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: completing the square revisited
Replies: 5   Last Post: Feb 28, 1998 8:23 PM

 Messages: [ Previous | Next ]
 Mike Bolduan Posts: 8 Registered: 12/6/04
completing the square revisited
Posted: Feb 24, 1998 10:52 PM

Although not directly related to apcalc I would be interested in
reactions to the following:

In an alg 2 class we have just gone through the whole process of
completing the square (i.e., converting a quadratic function to <<vertex form>>)
We then looked at how this same process could be used to find the
x-intercepts of the quadratic and eventually took a deep breath and plowed
through the "derivation" of what you and I fondly know as "The Quadratic
Formula". (Not too sure how successful that all was as the algebraic
simplifying got a bit heavy for many of the kids). Anyway, we ended up
with the statement that:

If ax^2 +bx + c = 0, then x = etc etc..

Here is my question (finally, they groan....):
I am insisting that the kids refer to this result as The Quadratic Theorem
and when asked for it (yes they do need to memorize it) they are to give me
back the ENTIRE sentence above, i.e., "if ....., then......". In some
(probably very small) way this might help them to understand that this is a
result that we actually proved to be true and is not simply some mishmash
of symbols that mean ol' Mr B (no relation to Mrs B...) is telling them to
memorize. Thoughts?

mike bolduan
The Catlin Gabel School
bolduan@catseq.catlin.edu
bolduan@aracnet.com

Date Subject Author
2/24/98 Mike Bolduan
2/25/98 Karen Hall
2/25/98 LnMcmullin@aol.com
2/27/98 Geoff Hagopian
2/27/98 NDianese@aol.com
2/28/98 Chris & Sheila King