# This is embarrassing, but need algebraic manipulation help... - Hewlett Packard

This is a discussion on This is embarrassing, but need algebraic manipulation help... - Hewlett Packard ; OK, all that crap you do--messing with fractions, rearranging variables, blah blah blah? The stuff you do in school then never do again, because the real world uses decimal points?! Well, my son is in the 7th grade, and he ...

# Thread: This is embarrassing, but need algebraic manipulation help...

1. ## This is embarrassing, but need algebraic manipulation help...

OK, all that crap you do--messing with fractions, rearranging
variables, blah blah blah? The stuff you do in school then never do
again, because the real world uses decimal points?!

Well, my son is in the 7th grade, and he is getting into that math--
pre algebra. Where can I get spun up quickly on using the step by
step algebraic manipulation powers of the HP-50? I really don't
intend to repeat the 7th grade, so I'm planning on letting the HP do
the heavy lifting

2. ## Re: This is embarrassing, but need algebraic manipulation help...

wolf_759@yahoo.com wrote:
>
> pre algebra. Where can I get spun up quickly on using the step by
> step algebraic manipulation powers of the HP-50? I really don't
> intend to repeat the 7th grade, so I'm planning on letting the HP do
> the heavy lifting

My first guess for a quick crash course would be the manual. My 48G
covers the topic quickly - I don't have a 50....

How is seeing the computer do something, even if it is step by step,
going to teach the thought process? I remember learning this stuff from
the teacher and the book - my parents didn't remember it either....

- Kurt

3. ## Re: This is embarrassing, but need algebraic manipulation help...

On Nov 9, 10:29 am, wolf_...@yahoo.com wrote:
> OK, all that crap you do--messing with fractions, rearranging
> variables, blah blah blah? The stuff you do in school then never do
> again, because the real world uses decimal points?!
>
> Well, my son is in the 7th grade, and he is getting into that math--
> pre algebra. Where can I get spun up quickly on using the step by
> step algebraic manipulation powers of the HP-50? I really don't
> intend to repeat the 7th grade, so I'm planning on letting the HP do
> the heavy lifting

"The real world uses decimal points" has nothing to do with finding
the value of x such that x^2 + 5x + 4 = 0, or knowing that there are
two of them. If you have decided that your son will go to vocational
school, then algebra may indeed be useless. But if he might end up
doing anything technical or scientific, being able to manipulate
simple equations and extract a value of a variable from the given
equation, by hand, might be very useful. It just depends whether he
is, or becomes, interested in how the world (governed by math,
physics, chemistry, biology ...) works.
So, rather than communicating that all that "blah blah blah" is just a
dumb ol' hoop you have to jump through, you would do him a service in
pointing out the fun of such activity. Perhaps a math tutor, who would
have some appreciation of how much fun it really is, would be a good
investment.
Irl

4. ## Re: This is embarrassing, but need algebraic manipulation help...

> How is seeing the computer do something, even if it is step by step,
> going to teach the thought process? I remember learning this stuff from
> the teacher and the book - my parents didn't remember it either....

I think it was more "dad" wants to have it step by step so he can
remember how to do it for checking work/teaching son. Not to give to
son to use.

TW

5. ## Re: This is embarrassing, but need algebraic manipulation help...

On Sat, 10 Nov 2007 06:30:39 -0800, Irl wrote:

>On Nov 9, 10:29 am, wolf_...@yahoo.com wrote:
>> OK, all that crap you do--messing with fractions, rearranging
>> variables, blah blah blah? The stuff you do in school then never do
>> again, because the real world uses decimal points?!
>>
>> Well, my son is in the 7th grade, and he is getting into that math--
>> pre algebra. Where can I get spun up quickly on using the step by
>> step algebraic manipulation powers of the HP-50? I really don't
>> intend to repeat the 7th grade, so I'm planning on letting the HP do
>> the heavy lifting

>
>"The real world uses decimal points" has nothing to do with finding
>the value of x such that x^2 + 5x + 4 = 0, or knowing that there are
>two of them. If you have decided that your son will go to vocational
>school, then algebra may indeed be useless. But if he might end up
>doing anything technical or scientific, being able to manipulate
>simple equations and extract a value of a variable from the given
>equation, by hand, might be very useful. It just depends whether he
>is, or becomes, interested in how the world (governed by math,
>physics, chemistry, biology ...) works.
>So, rather than communicating that all that "blah blah blah" is just a
>dumb ol' hoop you have to jump through, you would do him a service in
>pointing out the fun of such activity. Perhaps a math tutor, who would
>have some appreciation of how much fun it really is, would be a good
>investment.
>Irl

OK, pinheads, enough preaching. For one, you totally jumped to the
worn conclusion, but hey, whoever let that get in the way of getting
on their internet soap box? I'm an engineer, thank you very much, a
MS in Aero, not that matters. So, stick it up your pretentious ass if
you think that makes me or anyone else better than someone at a
vocational school. What's wrong with Vo tech?

I what the ability to CHECK his math, especially when I have a baby, a
full time job and don't want to spend too much time checking his
homework.

Thanks for the help, douchebag.

Mark Wilson

Change .org to .net to reply by e-mail

"If we lose the war in the air, we lose the war, and we lose it quickly."
--Field Marshal Bernard Montgomery

http://mysite.verizon.net/modelwerks/

RAAM FAQ:
http://mysite.verizon.net/modelwerks...FAQ/index.html

6. ## Re: This is embarrassing, but need algebraic manipulation help...

> OK, pinheads, enough preaching. For one, you totally jumped to the

Hope I wasn't included in that. I was going to answer when the
question first came up yesterday but didn't have time. Figured
someone else would have answered before I got around to it.

The step-by-step is pretty much useless. The only thing it works well
for is derivatives. Algebraic manipulations arent done step by step.
The only way to do it step by step is to manually divide, multiply and
so on in the equation writer. I'd recommend getting a review book for
algebra and using the calc to check once you remember what is going
on.

TW

7. ## Re: This is embarrassing, but need algebraic manipulation help...

Mark Wilson wrote:
>
> OK, pinheads, enough preaching. For one, you totally jumped to the
> worn conclusion, but hey, whoever let that get in the way of getting
> on their internet soap box? I'm an engineer, thank you very much, a
> MS in Aero, not that matters. So, stick it up your pretentious ass if

Management, huh? I think you need to chill out.

> I what the ability to CHECK his math, especially when I have a baby, a
> full time job and don't want to spend too much time checking his
> homework.

I still don't see how this helps teach anything to your son.

a) Most math books have the answer for either odd or even questions.
b) Son see's engineer father who has no interest in algebra - less
motivation for son to see it of any use in the real world (I'm an AOE
too and I use it all the time).
c) Most algebra problems at that level are single step, so going from
(a^2 - b^2) to (a - b)(a + b) in one step will teach him what,
exactly? The thought process is what matters, so checking the answer
and seeing it is wrong accomplishes nothing.

I think you'll be surprised just how quickly some of that stuff comes back
to you. I ended up getting diverted into software development for a number
of years before clawing my way back into engineering - the basics come
back pretty quick.

- Kurt

8. ## Re: This is embarrassing, but need algebraic manipulation help...

On Sat, 10 Nov 2007 17:28:21 -0800, TW wrote:

>> OK, pinheads, enough preaching. For one, you totally jumped to the

>
>Hope I wasn't included in that. I was going to answer when the
>question first came up yesterday but didn't have time. Figured
>someone else would have answered before I got around to it.
>
>The step-by-step is pretty much useless. The only thing it works well
>for is derivatives. Algebraic manipulations arent done step by step.
>The only way to do it step by step is to manually divide, multiply and
>so on in the equation writer. I'd recommend getting a review book for
>algebra and using the calc to check once you remember what is going
>on.
>
>TW
>

You were absolutely not included. I just for some reason found the
superior attitude of that one dork to be especially infuriating.
Maybe it was the implication that Vo Tech folks are nearly quite as
human as he thinks he is...

Thanks for the tip. I'll just have to slog through it.

Mark Wilson

Change .org to .net to reply by e-mail

"If we lose the war in the air, we lose the war, and we lose it quickly."
--Field Marshal Bernard Montgomery

http://mysite.verizon.net/modelwerks/

RAAM FAQ:
http://mysite.verizon.net/modelwerks...FAQ/index.html

9. ## Re: This is embarrassing, but need algebraic manipulation help...

On Nov 9, 7:29 am, wolf_...@yahoo.com wrote:
> OK, all that crap you do--messing with fractions, rearranging
> variables, blah blah blah? The stuff you do in school then never do
> again, because the real world uses decimal points?!
>
> Well, my son is in the 7th grade, and he is getting into that math--
> pre algebra. Where can I get spun up quickly on using the step by
> step algebraic manipulation powers of the HP-50? I really don't
> intend to repeat the 7th grade, so I'm planning on letting the HP do
> the heavy lifting

If you have any friends whose children went to school in other
countries, like Singapore, see if you can get one of their textbooks.
So many of the math, algebra books published here in the US are
garbage. It's no wonder the US is so far behind in basic math skills.
I'm horrible at math, always have been, always will be.
I took a look at a math text book that is in English, but published in
Singapore. It's amazing how clear some of the concepts are explained,
compared to the crap I had to struggle with when I was in
gradeschool.. My wife is from Eastern Europe and said the same when
she took classes here.

10. ## Re: This is embarrassing, but need algebraic manipulation help...

On Nov 9, 10:29 am, wolf_...@yahoo.com wrote:
> OK, all that crap you do--messing with fractions, rearranging
> variables, blah blah blah? The stuff you do in school then never do
> again, because the real world uses decimal points?!
>
> Well, my son is in the 7th grade, and he is getting into that math--
> pre algebra. Where can I get spun up quickly on using the step by
> step algebraic manipulation powers of the HP-50? I really don't
> intend to repeat the 7th grade, so I'm planning on letting the HP do
> the heavy lifting

Hey, cool! I'm doing pretty much the same thing with my daughter in
10th grade Alg 2/Trig. Here are some really quick suggestions -- not
necessarily what you asked for, but here's how it's worked for me in
practice.

First, it's worthwhile getting a (dead trees!) Schaum's outline that
covers the topics your kid needs. Using today's textbooks requires a
bit more sleuthing and cobweb-clearing than it sounds like you have
time. Schaum's shows full problem solutions, step-by-step, and and the
answers. Then it gives problem sets -- with all the answers, right
there on the same page. Then it gives supplementary problem sets -- I
forget whether it's with or without answers.

Anyway, that can help you clear the cobwebs and also be a great source
of extra problems if you "ruin" them as exercises by working the
assigned ones through with your kid. (Also, doing this, you will
acquire a fine understanding of which areas he/she needs more
practice, so come to the table well-armed!)

Back to the calculator -- the "step by step" thing in the HPs is
mostly for integration and differentiation, I believe. Run of the mill
polynomials are just simplified down -- it's not intended to teach you
anything.

However -- there are some things to do with your HP that will make it
pretty good as a support tool for your efforts.

First, check the flags. In MODE/CAS, be sure "Numeric", "Approx", and
"Complex" are unchecked and "Rigorous" is checked. (If you were doing
complex solutions, I'd have a program for you to switch between
"normal real life decimal" and "full-on hand-cranked answers for
humans" modes.) These will keep things in fractional form rather than
cranking out endless decimals, saving you the step of computing your
kid's answers for comparison (hence "Approx"; and more important, when
you enter "pi", it stays "pi" unless you really want to ->NUM it.
hence "Numeric".

Next, Equation Writer is your Friend. Normally, COLLECT and EXPAND
transform the entire symbolic expression, but you can run these from
inside Equation Writer and -- the magic -- they will only affect the
highlighted portion of the expression, not the entire thing. This
helps you avoid missing the intermediate stuff that you and your kid

Here's another cool tip: ->Q. That's the function that turns decimals
into quotients of integers. And -- believe it or not -- ->Q\pi (arrow,
Q, pi-symbol) does the same thing but digs out the pi values and
replaces them with the lowercase greek letter. OMG I can't tell you
how useful that is...

....So useful, in fact, that one of my subsidiary menus in my custom
menu hierarchy is defined just to make it easier to get to these:

%%HP: T(3)A(R)F(.);
\<< { { "A\<-\->N" {
\<< BLEEP "Use \<- or \->." DISPMSG
\>> $ALGF$NUMF } } { "\->Q(\pi)" { \->Q\pi PROPFRAC \->Q } }
{ "SIMPLIFY" SIMPLIFY } { "FACTOR" FACTOR } { "COLLECT" COLLECT }
{ "TSIMP" TSIMP } { "EQ\->" EQ\-> } { "EXLR" EXLR } { "FXND" FXND }
{ "DIVIS" DIVIS } { "SIMP2" SIMP2 } { "GCD" GCD } { "LCM" LCM }
{ "LVAL" LVAL } { "SUBST" SUBST } { "EMAT" EMAT } { } { "Main"
$RDJM } } GCST \>> Left-shift "Modes" puts the machine in symbolic-mode-for-kid-helping and right-shift "Modes" puts it back in Dad-needs-to-crunch-numbers mode. Note that left-shift-Frac does the integer quotient, right-shift-Frac does that with extra pie, and unshifted, it expresses the thing as a proper fraction. ("Main" takes me back to the root of my custom hierarchy.) Oh, all right, here are the mode flippers. I keep these in HOME so they're accessible from anywhere. (I do the dirty work in a subdirectory so I don't need to clean anything up when I use the thing for my stuff.) Here's$ALGF:

%%HP: T(3)A(R)F(.);
\<< { -1 -2 -3 -22 -52 -79 -105 -114 -116 -119 -120 -128 -123 -125
-128 61 } CF { -20 -21 -27 -99 -100 -103 -109 -111 -112 -113 -115
-125 } SF "Flags set for algebra." DISPMSG
\>>

Here's $NUMF: %%HP: T(3)A(R)F(.); \<< { -1. -2. -3. -22. -27. -109. -105. -112 -115 -125. -128. } SF { -20. 21. -52. -79. -99. -100. -103. -111. -112. -113. -114. -116. -119 -120. -123. 61 } CF "Flags set for numeric calc." DISPMSG \>> ....and GCST, since it's used in the example: %%HP: T(3)A(R)F(.); \<< \-> mnu \<< PUSH HOME mnu MENU POP \>> \>> It makes things work properly when you're working in a subdirectory and flipping through custom menus defined in HOME. Hope some of this helps. Pedantry, anyone? :-) 11. ## Re: This is embarrassing, but need algebraic manipulation help... P.S. I hate to do this, but I have one more suggestion for you: Get on the TI site and buy yourself a TI-Nspire CAS calculator. Yeah, it's$160 or so. Yeah, it's TI. No, it won't be your primary computing
device. No, you probably won't want to supply it to a 7th grader.

Just consider this, though.

The function graphs on that thing are amazing. One thing it does
really, really well is shading inequalities. (Figured this one out
myself -- it's not intuitive. In fact, the whole calculator is pretty
much not intuitive and just plain nasty to navigate. But I digress...)
You can stick a couple of line equations, or polynomials, in there,
use less-than or greater than instead of an '=' sign, and dang if that
machine doesn't draw perfectly zoomed, beautifully shaded graphs. And
though. "Pretty" is also part of "pretty small".)

Yeah, you can do all the usual symbolic manipulation, but the machine
has better control over step-by-stepping it and a more pedantic mode
of interaction. But the really nice thing -- for what you need to do
-- is that you can sit down with the kid's homework, punch in each
problem, and save each problem's results in a way that makes reviewing

The NSpires let you create a document (that's the whole homework
assignment" and, within that, problems (one for each homework
problem), and within each problem, separate pages (one for the
calculator log, one for the graph, another one for the other graph
when you want to show a variation, etc.)

Then, once you've been through everything, you can sit down with the
kid and say things like "see how you did that? This is what it's
supposed to look like" and wave the thing in front of them. Or huddle
over it together and mess around with it. Or whatever. And when the
kid re-does a problem but still gets it wrong, you get to refer to all
the steps you saved when you solved it so see where he/she went wrong
further along in the problem.

Which means that... if get so busy that you can't afford the time to
go over the homework now and then, you can scan or copy the kid's work
and do your prep work with the NSpire while you're somewhere else
(waiting for a meeting to start, for instance) so that you can get
through it all with the kid in the half hour that you *can* make
available that evening. (Or something like that.)

But -- keep the HP close at hand. As tempting as the TI may seem, the
NSpire will be good for some things but the HP will be better for most
everything else. Think of the NSpire as a \$160 whiteboard with a
"recording" feature.

Was that on topic or off-topic?

-^-rdj-^-

12. ## Re: This is embarrassing, but need algebraic manipulation help...

On Mon, 19 Nov 2007 12:02:20 -0800 (PST), rdj
wrote:

>But -- keep the HP close at hand. As tempting as the TI may seem, the
>NSpire will be good for some things but the HP will be better for most
>everything else.

Really?.. .For what, for example?...

A.L.