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Topic: how do you factor this?
Replies: 3   Last Post: Oct 15, 2012 6:41 PM

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 jdmgt Posts: 1 Registered: 10/11/12
Re: how do you factor this?
Posted: Oct 11, 2012 6:03 PM

On Oct 11, 12:01 pm, stoneboy <x...@x.com> wrote:
> Hi, I am teaching my daughter how to factor equations and came across
> an expression  in a worksheet that looks like below:
>
> 1+a+b+c+ab+bc+ca+abc
>
> The answer given (no work shown) shows (a+1)(b+1)(c+1) would be the
> factors.  Sure enough, when I multiply all those terms, eventually, I
> get the above result.  How do I go about deciphering how to group and
> factor the original equation above.  Kinda confused.  I was able to
> group them and factor somewhat, but could not get it down to the
>
> Thanks
>
> s

Let's form 4 groups: a+1 + ab+b + ac+c + bc+abc = (a+1)+b(a+1)+c(a
+1)+bc(a+1)= (a+1)(1+b+c+bc)=(a+1)[b+1 +c(b+1)]
Finally: (a+1)(b+1)(c+1)

Date Subject Author
10/11/12 justlooking for someone else
10/11/12 jdmgt
10/11/12 justlooking for someone else
10/15/12 Ken.Pledger@vuw.ac.nz