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Topic: Simplifying Algebraic Expressions with Subtracted Expressions
Replies: 67   Last Post: Nov 25, 2013 12:57 PM

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 Bishop, Wayne Posts: 2,881 Registered: 12/6/04
Re: Simplifying Algebraic Expressions with Subtracted
Expressions

Posted: Nov 25, 2013 12:49 PM

Yet again, don't use the implication symbol in place of the equality
symbol (or vice versa which I too often see as well) and advise the
first that explain EQUALITY by use of the distributive law. And
again, sharpen up your language, you don't "solve" an expression by
simplifying it or, as in this case, expressing it in a LESS
simplified form in order to explain why something works. But, even
if the expression reduces to a constant, you have not "solved it",
you've merely express it in a different, much simpler,
form. Teachers are teaching with every word they speak,
mathematically good, mathematically accurate but awkward, even
mathematically wrong.

Wayne

At 06:21 PM 11/11/2013, MVTutor wrote:
>How would you advise students in the example "1-(x+2-3)"?
>Can I tell them to drop the parentheses and reverse the signs of each term?
>Is the explanation that if we change the subtraction to an addition
>we can use the associative property of addition?
>Are there alternative methods?
>I've seen one book that suggests solving it as follows:
>1-(x+2-3) => 1+ -1(x+2-3)=> then solve -1(x+2-3)
>- -1(x)+-1(2)- (-1)(-3)
>but this seems a bit confusing to me.
>Any suggestions?
>Thanks, --John

Date Subject Author
11/11/13 MVTutor
11/11/13 Robert Hansen
11/12/13 Bishop, Wayne
11/12/13 MVTutor
11/13/13 Jonathan J. Crabtree
11/13/13 Bishop, Wayne
11/14/13 Joe Niederberger
11/14/13 Robert Hansen
11/14/13 Joe Niederberger
11/14/13 Robert Hansen
11/14/13 Joe Niederberger
11/14/13 Robert Hansen
11/14/13 Louis Talman
11/14/13 Joe Niederberger
11/14/13 Robert Hansen
11/14/13 Robert Hansen
11/16/13 Bishop, Wayne
11/16/13 Robert Hansen
11/14/13 Joe Niederberger
11/14/13 Robert Hansen
11/16/13 Bishop, Wayne
11/14/13 Pam
11/15/13 Robert Hansen
11/15/13 Joe Niederberger
11/15/13 Robert Hansen
11/15/13 Joe Niederberger
11/15/13 Joe Niederberger
11/15/13 Joe Niederberger
11/15/13 Robert Hansen
11/16/13 Bishop, Wayne
11/16/13 Robert Hansen
11/17/13 Bishop, Wayne
11/17/13 Robert Hansen
11/17/13 Bishop, Wayne
11/15/13 Joe Niederberger
11/15/13 Robert Hansen
11/15/13 Pam
11/15/13 Robert Hansen
11/15/13 Pam
11/16/13 Robert Hansen
11/16/13 Robert Hansen
11/16/13 Joe Niederberger
11/16/13 Robert Hansen
11/18/13 Louis Talman
11/21/13 Robert Hansen
11/21/13 Louis Talman
11/16/13 Pam
11/16/13 Robert Hansen
11/16/13 Pam
11/16/13 Robert Hansen
11/18/13 GS Chandy
11/17/13 GS Chandy
11/17/13 Pam
11/17/13 Robert Hansen
11/17/13 Pam
11/17/13 Robert Hansen
11/17/13 Pam
11/18/13 Robert Hansen
11/18/13 Robert Hansen
11/18/13 Pam
11/18/13 Robert Hansen
11/25/13 Bishop, Wayne
11/25/13 Robert Hansen
11/22/13 Joe Niederberger
11/25/13 Bishop, Wayne
11/23/13 GS Chandy
11/24/13 Robert Hansen
11/25/13 Bishop, Wayne