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Vanity... 4 [4 - 5x] = 6x + 4
high school ^ | n/a | n/a

Posted on 01/09/2012 9:45:26 PM PST by The SISU kid

I know there a a lot of FReepers smarter than I, so here goes...got this presented to me for help & I for the life of me am stumped

4 [4 - 5x] = 6x + 4

says answer is x= 10/7

can someone show how to solve?

Thanks in advance....


TOPICS: Cheese, Moose, Sister; Education
KEYWORDS: algebra; highschoolmath; math
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To: Jonty30

I just finished taking a basic math class, before jumping into something more difficult. I understood the math. My problem was learning how to use the calculator. My learning curve was different than the 19 year olds in my class who could plug the numbers in, but had no understanding of why.


41 posted on 01/09/2012 10:39:36 PM PST by Betty Jane
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To: All

UPDATE: 10/7 is the answer....thru a text message misinturppration...

4 abs(4 - 5x) = 6x + 4

I assumed the absolute values marks were brackets....my bad


42 posted on 01/09/2012 10:40:43 PM PST by The SISU kid (I feel really homesick all the time & so do all the other aliens.....)
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To: Ingtar

the link you posted says the answer is 6/13


43 posted on 01/09/2012 10:41:13 PM PST by USNBandit (sarcasm engaged at all times)
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To: Betty Jane

let me guess....polish notation? :)


44 posted on 01/09/2012 10:41:49 PM PST by The SISU kid (I feel really homesick all the time & so do all the other aliens.....)
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To: FrogMom

Its either your number, or 42.


45 posted on 01/09/2012 10:44:50 PM PST by FlyingEagle
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To: USNBandit

think he meant that as a quote from my original post....


46 posted on 01/09/2012 10:45:04 PM PST by The SISU kid (I feel really homesick all the time & so do all the other aliens.....)
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To: The SISU kid

.223


47 posted on 01/09/2012 10:45:54 PM PST by bobby.223
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To: FlyingEagle

“Its either your number, or 42.”

Of course.....Life, the universe and everything! :)


48 posted on 01/09/2012 10:46:12 PM PST by The SISU kid (I feel really homesick all the time & so do all the other aliens.....)
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To: Pikachu_Dad
Yes, fixed that error in the second post

I saw that later as I read down through the posts.
49 posted on 01/09/2012 10:52:49 PM PST by aruanan
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To: Betty Jane

I hate calculators, because they weaken our skills. They are great for speeding up things, but horrible for increasing our math skills.

If it were up to me, calculators would be banned until college, to which you’d then take a first semester course on how to use one.

I think you should have to know how to do everything with a pencil, sheet of paper, and the appropriate charts.


50 posted on 01/09/2012 10:54:30 PM PST by Jonty30 (What Islam and secularism have in common is that they are both death cults.)
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To: The SISU kid
One of my favorite solutions;

http://www.cyberiapc.com/gallery/pic_details.php?pid=168

I was also able to solve the Towers of Hanoi mathematical puzzle in one move. A B-52 airstrike.

51 posted on 01/09/2012 11:02:25 PM PST by Hillarys Gate Cult (Those who trade land for peace will end up with neither one.)
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To: The SISU kid

For abs value the answer is both. x=10/7 and x=6/13.


52 posted on 01/09/2012 11:04:57 PM PST by PeaceBeWithYou (De Oppresso Liber! (50 million and counting in Afghanistan and Iraq))
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To: The SISU kid

I had to go look up Polish notations. The class I took was Contemporary Mathematics. It’s pretty much math for real life. The class touched on interest rates, loan payments, compounding interest, basic statistics, apportionment, set theory, means, modes, etc. I understood all that.

Jonty30, I absolutely agree about learning how to do the math before using a calculator. I had never touched a TI-84. I didn’t know how to turn the darn thing off. That was much easier to learn for me, than the necessary math for some of the kids. They could enter the numbers, but didn’t know how they were related.


53 posted on 01/09/2012 11:10:48 PM PST by Betty Jane
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To: NCDave

I’m just glad it was trying to figure out 7x13!

http://www.youtube.com/watch?v=0K-yV91PBbE


54 posted on 01/09/2012 11:11:20 PM PST by 21twelve
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To: Ingtar
says answer is x= 10/7

Nope. Wolfram gets 6/13.

http://www.wolframalpha.com/input/?i=4[4-5x]+%3D+6x%2B4

55 posted on 01/09/2012 11:22:59 PM PST by cynwoody
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To: MHGinTN
What do you end with if you divide both sides by 4 to start?

Same answer.

4 - 5x = 1.5x + 1
3 - 5x = 1.5x
3 = 6.5x
6 = 13x
6/13 = x

56 posted on 01/09/2012 11:31:48 PM PST by cynwoody
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To: The SISU kid

We have found many many errors in the problem sets in math and science textbooks at the high school and college level - advanced physics, calculus, statistics. My chemistry major son has sometimes spent hours trying to get the same answer as the text only to have my mathematician husband take some time and say, yep text is in error.

But with something as simple as this the teacher ought to be confident and capable enough to know right away that the text is in error. If the problem is much harder than it ought to be - maybe there’s an error. If three people working independently get the same different answer, maybe there’s an error.

The publishers keep churning out new texts because it is so lucrative - they’d do better to correct the errors in the old ones. Basic algebra is basic algebra - does not need the text rewritten!


57 posted on 01/09/2012 11:43:47 PM PST by heartwood
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To: The SISU kid

58 posted on 01/09/2012 11:52:20 PM PST by Drango (A liberal's compassion is limited only by the size of someone else's wallet.)
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To: Ingtar

re: Checked with http://www.wolframalpha.com/bing/?i=4(4+-+5x)+%3d+6x+%2b+4

Great link, thanks.


59 posted on 01/10/2012 12:26:22 AM PST by joe212
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To: heartwood

Talk about hours and hours of figuring something out reminds me of college. We had a Russian prof that was THE expert in electromagnetic theory. We didn’t have a text book - it was all taken from his presentations. Which were almost entirely oral.

At the end of various sections we would have to write an essay on whatever it was we had learned, with how it applies, what it means, how to calculate, etc.

In putting together one essay I realized that I did not have a very good understanding on the difference between “edge” lines and “H” lines. So I went through my notes and tried to figure it out - I recall putting things in columns under the appropriate columns of “Edge” and “H”.

Working late into the evenings and much knashing of teeth and pulling of hair I thought I had it finally figured out; in spite of the overlaps in the columns. Proudly handed in my essay (8 to 10 pages I imagine?). The teacher’s assistant handed it back the next day and chuckled. “You and half the class came up with similar essays. However - there is no such thing as “edge” lines - that was just him slipping in and out of his pronounciation of “H” lines. You have until Friday to fix it.”

AAAAAAAGGGGGGGGHHHHHHHH!

With my kids in grade school and Junior High, if the question seems oddly worded (lots of word problems nowadays, and I think this math guys are often lousy at English) I will have my kids explain what they think the problem means first to “correct” the error, and then solve the problem based on their assumption rather than pulling their hair out!


60 posted on 01/10/2012 12:31:06 AM PST by 21twelve
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