OK-HELP!!!!!
I'm good at many things- I have talents- math is not one of them
I am stuck- I should probably get this- I will probably slap my forehead when I do get it-
this is basic elementary algebra stuff- (yes I'm a college senior- no laughing out loud)
linear inequality
I'm having trouble at the very start
I'll give you some examples
no exponents but will use / to denote a fraction
also < or > and =to, I don't have a combination key for less/greater than or equal to, so you'll have to picture it
1) 6x-5 < or = to -1/3x -4
2) -8w -5 > or =to 1/3w -6
3) -3/5t +6 < -6t -8
4) 8y +4 < 5/4y +6
5) 6x -5 < or =to -1/3x -4
6) -7x +4 > 8/3x -8
this stuff
now I get the reducing part the (PEMDAS) or whatever
but how do I know which/where to begin
look at #1 because I looked at the answer(I'm using a computer math program) I know that 1st I have to add 1/3w to each side
for #2 how do I decide/know I have to add 8w to each side to begin
for #3 how do I decide/know I have to add 6t to each side
do you get what I'm asking?
completing the problems makes sense to me--- it's getting started that is driving me crazy for some reason!
look at #1 again
6x -5 < or =to -1/3x -4
first add 1/3x to each side(how do I know to add 1/3 instead of going with the opposit of positive 6x which would be -6x)
then combine the like terms
then get rid of the -5 by adding 5
then multiply
to get the answer of x<or =to 3/19
so on that level I get it but :taz:
Oh I'm loosing my mind
If anyone knows about the Aleks math program and can email me through it -- or try to help here-- I will love you forever!
Thanks
Unfortunatly my brain isn't wired for math either... :-[
so I can just give you :hug:s
/D
It doesn't really matter which side you eliminate the unknown variable from. It's just slightly more convenient to do it so as to have it remaining on the side where it is positive.
e.g. here's doing 1 the "long way"
6x-5 <= -(1/3)x -4
(subtract 6x)
-5 <= -(19/3)x-4
(add 4)
-1 <= -(19/3)x
(multiply by 3/19)
-(3/19) <= -x
(multiply by -1, remembering doing this reverses the inequality condition)
(3/19) >= x
(rewrite in equivalent form)
x <= 3/19
same answer as the other way of working...
6x-5 < or = to -(1/3x) -4
(add (1/3)x to both sides )
(19/3)x-5 <= -4
(add 5)
(19/3)x <= 1
(multiply by 3/19 )
x <= 3/19
You get exactly the same result either way (maths is like that ;) ) , but the working is slightly easier. The important thing is to eliminate the unknown variable from one side of the inequality.
Does that answer the question?
(Be back in an hour or so).
P.S. Linus in Peanuts reckoned that in algebra x is almost always 9, and y almost always 11. I've found this advice invaluable over the years.
Here's my approach to equations and inequalities in general ('cept for the more esoteric stuff), and especially for linear ones. Of course, the more mathematical weirdness you throw in, the more wrong this approach gets, but it's fine for linear things.
1. I have a bunch of stuff in (in)equality.
2. My goal is to get my variable on one side and all the other crap on the other.
3. What I do to one side, I have to do to the other.
4. If things get simpler, I know I'm making progress.
So, since beagle did such an admirable job of #1, I'll take #2.
-8w -5 ≥ (1/3)w -6
This conforms nicely to #1.
First, I'm going to add 6 to each side. I could add any number of any other things arbitrarily, but I happened to choose 6 because that would conveniently add with -6 on the right side of the inequality to give me a result with no constants. After doing the same thing to the left side as per #3, I'm left with:
-8w +1 ≥ (1/3)w
Now, since the ONLY thing on the right side is (1/3w, I know that I'm making progress, as per #4, because (1/3)w is simpler than (1/3)w -6, and -8w +1 is no more complex than -8w -5 was.
Since, as per #2, my goal is to get x alone on one side, I'm now electing to add 8w to each side. That way, on the left side, I only have a constant (as opposed to a constant and a variable, so it's simpler and better), and on the right side I only have a variable with coefficient, which is no more complex than a variable with a different coefficient. If I had chosen to subtract (1/3)w, I would have made no progress, because my left side would be just as complex as it was before, and my right side would now contain a 0 which, just like (1/3)w, is a single term. If I had chosen to subtract 1, then my left side would be simpler, but my right side would become more complex, so I wouldn't have accomplished much. Anywho, I'm left with:
1 ≥ (25/3)w
Now, I just have to divide by (25/3), which is the same thing as multiplying by (3/25), and I'm left with:
3/25 ≥ w or w ≤ 25/3, whichever you prefer.
My steps in summary:
-8w -5 ≥ (1/3)w -6
-8w +1 ≥ (1/3)w
1 ≥ (25/3)w
3/25 ≥ w
In reverse, i.e. moving the "w" around before the constants, this would've been
-8w -5 ≥ (1/3)w -6
-5 ≥ (25/3)w -6
1 ≥ (25/3)w
3/25 ≥ w
If I had gone the "other way," i.e. adding 5 and subtracting (1/3)w, this would've been
-8w -5 ≥ (1/3)w -6
-8w ≥ (1/3)w -1
(-25/3)w ≥ -1
w ≤ 3/25 N.B. In this step, I had to flip the inequality sign, because I was dividing by a negative number.
Does that help at all?
Oh, for the record, I assumed that 1/3w meant "one third w," not "one divided by [three times w]."
This stuff is the little that makes much sense to me.
3) -3/5t +6 < -6t -8
-6 -6
-3/5t<-6t-14
-3
-7x +4 > 8/3x -8
My philosophy is always go for the minus and always make it look nicer
so ..... .....work on the minus and make it look nicer
add 8 to both sides
12 -7x > 8/3x
next step : get the x on one side only so that it looks even nicer
so..... add 7x to both sides
12 > 7x + 8/3x
next step: reduce it to one instance of x so it looks nicer
so....... take the x outside some brackets
12 > x (7 + 8/3)
sort out the silly way the stuff inside brackets looks
12 > x ((7 x 3) + 8/3)
--------
3
is
12 > x (21+8)
-------
3
12 > x (29)
----
3
brackets look silly now so make it look nicer
12 > 29x
---
3
ugh it can look better than that, move the 3 by multiplying both sides
12 x 3 = 29x x 3
---
3
ooo threes on right hand side cancel out so it looks even better
36 > 29x
want x alone - need 29 under to cancel out so do that both sides
36 > x
---
29
hmmm prefer x on right really so change signs and swap
x <= 35
---
29
dont like fractions? get decimal equivalent of 35/29 !!
Method: eliminate minuses first, do both to same side, divide or multiply by thing you want to move sides or cancel out, and always think what would make it look nicer
Quote from: Griffin NoName on September 16, 2007, 12:32:38 AM
and always think what would make it look nicer
Hehe... at this point, my definition of "nice" is so warped... :mrgreen:
I just go for simple. If I get into making things look nice, I'm liable to re-express things using trigonometric identities.
Quote from: Alpaca on September 16, 2007, 01:28:57 AM
Quote from: Griffin NoName on September 16, 2007, 12:32:38 AM
and always think what would make it look nicer
Hehe... at this point, my definition of "nice" is so warped... :mrgreen:
I just go for simple. If I get into making things look nice, I'm liable to re-express things using trigonometric identities.
::) back in my younger days I'd have gone for a Fourier look good factor - now I like the quiet life ::)
Quote from: anthrobabe on September 15, 2007, 08:13:25 PM
OK-HELP!!!!!
I'm good at many things- I have talents- math is not one of them
Nor is English. It is maths (or better still mathematics). For goodness sakes can we not have a bit more respect for the mother tongue from our former colonies.
yours pedantically and imperialistically,
Duke Goat
Goatie, we in the New World simplify it and reduce it to math. Not maths. The full word is mathematic, so the shortened form could well be math (no extraneous s). With all the s's saved, you could combine them with all the u's ya'll overuse, and spell us a LOT...
By the way, the mathematical language expressed here might as well be Swahili to me. I don't understand it, and what's worse, I no longer want to!!
Old, lazy and proud of it! :mrgreen:
the full word is mathematics (note s)
I have to agree with Goat. The full word is mathematics.
Mathmatic would be, well, like asthmatic, or something.
It would help if American English was not called English :mrgreen:
Perhaps we ought to chalk it up to differences in dialects? :)
Mathematics-al formulas?
Hmmph...
It is the plural in Spanish too: Matemáticas
(mathematica is/was a math software).
Quote from: Sibling Chatty on September 17, 2007, 03:31:20 AM
Mathematics-al formulas?
Hmmph...
Now you've got me thinking about sheep.
math
mathematical
it just doesn't compute
(evidently English doesn't either)
Oh well
Thanks everyone--- it will eventually click
It is just basic algebra. If you feel to confused with inequations try solving some basic equations first. The basic principle is: what goes on the left also goes on the right.
x + 4 = 16
x + 4 - 4 = 16 - 4
x = 12
That is the basic principle, that applies to algebra and to inequations. The only difference is the change of direction of an inequality while dividing by a negative (as the siblings mentioned before):
-7x >= 21
-7x 21
----- <= ------
-7 -7
x <= -3
Hope that helps.
Quote from: Sibling Chatty on September 17, 2007, 03:31:20 AM
Mathematics-al formulas?
Hmmph...
Linguistics -> linguistical
Gymnastics -> gymnastical
Actually I agree with you. A small country off Europe gets half the world to use its language, then complains about a few spelling changes.
On the other hand why simplify maths to math and then wreck it by changing use to utilize? ;)
heaven forfend that we should object to all of our fabulous inventions being mucked up by johnny foriegner!
football, rugby, rounders, spelling etc!
Quote from: goat starer on September 18, 2007, 01:55:44 PM
heaven forfend that we should object to all of our fabulous inventions being mucked up by johnny foriegner!
football, rugby, rounders, spelling etc!
... iron-fisted world domination... ::)
;D
Dear Goat,
I revel in mucking about!
I refuse to color inside the lines!
What the heck is a rounder? (is it the traffic thing- thought that was a round about?)
And a boot goes on ones foot- :devil2:
Sincerely,
The colonist
;)
So far with this basic mathematics :mrgreen: class I've done well- grasped things more or less- just hit a wall for a bit- seems to have passed for now and I'm moving along again.
I haven't taken any sort of mathematics classes since the early 1980's so it is really a new thing for me.
Thanks to all for the maths tutoring.
luv me
Rounders is a game the colonists messed about with and renamed baseball. :)
Quote from: The Meromorph (Quasimodo) on September 18, 2007, 05:30:45 PM
Rounders is a game the colonists messed about with and renamed baseball. :)
:devil2: yes, I did a google search and decided to muck about with it anyway :devil2:
since we have no real poking something with a stick avatar I'll utilize this one for now
:donatello:
Big Hint--- this colonist would like a poking with stick smilie--- pretty please. I'll be good
rounders is a GIRLS game that became the national sport for men in the states. :goldfish:
back to the maths....
I dont understand a word of this but i do know my 12 times table if that helps
You're ahead of me. I was changing schools when times tables were beaten into heads, and I never memorized them. I can multiply by 9 with little problem, but otherwise, it's calculator time.
I can add in my head, though, because of scoring for Scrabble.
Still, it's difficult for me because of the whole dyslexia mess. Numbers just don't sit still well, and if they keep changing as I work on a problem, it makes it hard.
ROUNDERS is the BEST game in the world.
Quote from: Sibling Chatty on September 25, 2007, 01:10:00 AM
You're ahead of me. I was changing schools when times tables were beaten into heads, and I never memorized them. I can multiply by 9 with little problem, but otherwise, it's calculator time.
I was never big for memorization; I always liked to work things out. For me, this meant I did really well in physics (I only had to memorize a couple of equations, and then would quickly derive everything else that I'd need) but lousy in biology and chemistry, where you can't "work out" the names of the parts of the cell, or what colour the precipitate is when you dissolve compound X in solution Y.
Quote from: Griffin NoName on September 25, 2007, 01:20:25 AM
ROUNDERS is the BEST game in the world.
i have seen some controversial statements on websites but this one takes the biscuit! Ban yourself for being a troll!
Quote from: goat starer on September 25, 2007, 05:08:46 PM
Quote from: Griffin NoName on September 25, 2007, 01:20:25 AM
ROUNDERS is the BEST game in the world.
i have seen some controversial statements on websites but this one takes the biscuit! Ban yourself for being a troll!
What's your problem? If the heat's too great get out the kitchen.
Apologies. What I should have said was:
ROUNDERS is the BEST
sport in the world. (Ref. http://en.wikipedia.org/wiki/Rounders (http://en.wikipedia.org/wiki/Rounders)).
The best game in the world used to be Strip Trivial Pursuits...
I have found compelling evidence to support the view that rounders is a silly game
http://www.showcase.commedia.org.uk/article/view/547/1/1/ (http://www.showcase.commedia.org.uk/article/view/547/1/1/)
Quote from: Sibling Chatty on September 26, 2007, 03:11:54 AM
The best game in the world used to be Strip Trivial Pursuits...
I think a Trivial Pursuit Drinking Game could be entertaining... and make it a bit harder to win.
I'm not sure which I like better:
- get a piece of pie, do a shot
- miss a pie piece question, do a shot
;D
Quote from: Sibling Lambicus the Toluous on September 26, 2007, 02:39:28 PM
Quote from: Sibling Chatty on September 26, 2007, 03:11:54 AM
The best game in the world used to be Strip Trivial Pursuits...
I think a Trivial Pursuit Drinking Game could be entertaining... and make it a bit harder to win.
I'm not sure which I like better:
- get a piece of pie, do a shot
- miss a pie piece question, do a shot
;D
just do shots---
I know I'm in the right place when a mathematics question turns into fisticuffs over the silly to non-silly ratio of rounders and the merits of strip trivial pursuit---
Oh I'm in the right place!!!
Quote from: goat starer on September 26, 2007, 11:20:15 AM
I have found compelling evidence to support the view that rounders is a silly game
http://www.showcase.commedia.org.uk/article/view/547/1/1/ (http://www.showcase.commedia.org.uk/article/view/547/1/1/)
But who would agree with someone who prefers Bush to Nixon?
Apologies Anthrobabe :offtopic:
Off topic? No such critter...
This is the home of mixed topic conversation!
Rounders seems to be similar to softball, which I LOVE, and played for years--and only broke one bone playing, as opposed to stupid volleyball, where I broke my foot twice, then broke two fingers.
And the combo of strip Trivia with a drinking game was tried more than once.... :halo: Correct answer, you get a shot of your choice, incorrect answer, you have to either give up one piece of clothing OR take a shot of the other team's choice.
Wist sufficiently bad gin and a really strong team, you can end up with a roomful of drunken, mostly naked people :barf: :barf: :barf: :barf: :puke: :puke: :puke: while you :ROFL: :ROFL: :ROFL: (We used to play four teams, 3 to a team...)
If we ever get to play that game around here I want to be in your team... :D
And yes, I know my trivia...
I also have managed to be disqualified in pictionary for being "too good" :-[ and was demoted to become the judge. :(
I did well in most subjects at school but I had three things I hated and dreaded equally: Mathematics, Grammar (Swedish and English alike) and Physical Education...
Funny enough, even though I disliked Math so much, I really liked Chemistry, Biology and Physics. Of cause at that particular level the first two aren't so closely knit to math as they becomes later on at higher levels. Physics was however the reason I finally learned how to do equations... unfortunately I have forgot all about them now. :-[
Quote from: Griffin NoName on September 26, 2007, 10:22:00 PM
Quote from: goat starer on September 26, 2007, 11:20:15 AM
I have found compelling evidence to support the view that rounders is a silly game
http://www.showcase.commedia.org.uk/article/view/547/1/1/ (http://www.showcase.commedia.org.uk/article/view/547/1/1/)
But who would agree with someone who prefers Bush to Nixon?
Apologies Anthrobabe :offtopic:
:halo:
he is a goat-- they eat paper and tin cans and stuff- that's the problem
;)
girl game my foot- I'll show 'em a girl game
(yes, my inner pirate is showing :yar:)
BTW I think I'm catching some of this MATH stuff--- if I can retain it long enough to pass the exams I'll be fine- yes, I'd like to retain it forever but will be happy to do well in and pass the class.
I'm stubborn if nothing else- it's computer based (the class) and so far in 6 weeks I've logged like 90 hours online.
Darn!!!
You guys have had a math thread and I'm just now finding out about it?
*^$&()&%#^(%#...
it's also known as the 'bang head here' thread (at least for me)--- I'm doing it- the math, it'll sink in and hopefully stick long enough to finish my degree.......
I despise math--which I am doing right now.
I will be so glad when I'm done--only stats and calculus left. Yay for a BA (versus a BS, which would require far more math)!