OT: math people....

[mystikal star]

Does anyone here know Distributive Property? If so...can you help me out?

[izzybee]

What type of math is it? My dad has laods of books on it if that helps. I could find some info. What kind of thing is it tho? Is it calcullus or statistics or?????? sorry I could be much of a help!

[rhinoseri]

Well, distributive property is basically:



a(b+c)=ab+ac
so...
2(3+4)=6+8=14


That's just basically what it is, but I'm not sure exactly what you need to know about it.

[kentuckygalrk]

Well... hopefully this helps. First it's imporant to know the rules for solving the problems and you always do the arithmatic in this order...
#1 ~ALWAYS solve what's in the parenthesis first!
#2 ~ next do all multiplication and/or division
#3 ~ last do addition or subtraction


examply 1
a(b+c)
3(2+5)=
3(7)=
21


example 2
6 + 2(5+6)=
6 + 2(11)=
6 + 22 =
28


example 3 (a little more complicated)
7(11-8) + 3(10+6) -5=
7(3) + 3(16) -5=
21 + 48 -5=
69 - 5=
64


If you need anymore help... let me know!
~Rachel

[kentuckygalrk]

Oh... and I know what Rhinoseri was doing... that is only when the terms inside the parenthesis are not like... for example, if the problem is 2(6-4x) then you multiply each termand it becomes,


2(6-4x)
12-8x


another example is
3(5+4+8x)
15+ 12+ 24x=
27 +24x
*If there is a variable such as "x" and you have to multiply, be sure to multiply EACH term first


However, always look to make sure there's not a "double parenthesis" too as in the next example because if there's something inside a parenthesis that you can solve... you must solve that first.
2(6+3x+{2+3})=
2(6+3x+5)=
12+6x+10=
22+6x


I hope I'm not confusing you too much... perhaps if you have a specificproblem I can help you solve I'm more than happy to do so


~Rachel

[mystikal star]

Thanks so much!!! Finally understanding it but now I'm stuck again with equations. I'll post a couple and maybe you can help me.


a.) -7x - 24 = -129


b.) 3(2y - 3) = 27


c.) 9(y + 2) = 3(y - 2)


d.) 8y + 4 + 18 = 4y - 6


Can anybody help me understand problems like that? I'm REALLY stuck.

[mystikal star]

Okay I think I'm understanding these now, but I want to check my answers before I turn them in. Can I check with one of you who posted for me earlier and you can tell me if they are right?

[Jenneh]

i dont really understand what you have to do...... lol. do you just have to tke the brackets away or do smthing else to it?


if i was given this equation i'd solve it by...


C.) 9(y + 2) = 3(y - 2)


= 9y+18 = 3y - 6 (minus 3y from the right so you have to minus 3y from the left)


= 6y+18 = -6 (plus 6 from the right so you have to plus 6 to the left)


= 6y + 24


is that what you have to do in the end or not?


Jen xxxx

[mystikal star]

Yes Jenneh!! How do you know that? Like when there are lots of numbers like in letter D above, how do you know what number to subtract/divide/multiply/add first? You know what I'm asking? I cant explain it. Like on letter D how do I know if I divide 8y or minus 4 first? I hope you understand what I'm asking.....

[2jo2]

It's an equation, meaning equal on both sides of the = .....


No matter what function you perform first, it doesn't matter, as long as you do the same thing to each side of the =. I think what you're asking as in the example D, is how do you know which to do first, you need to group the like with like.


8y + 4 + 18 = 4y - 6


So first you group the like with like... meaning move all the regular numbers on one side of the = and then move the variables on the other side. Like this:


4+18+6=4y-8y


See, I just added 6 to each side and subtracted 8y from each side, just moving everything around. Then you just perform the functions on each side of the = separately:


4+18+6=28 and 4y-8y=-4y and then you put those equal to each other to complete the problem:


28=-4y


Next you look at the problem to see if you can break it down any more, if the numbers are divisable by each other, which they are. 4 goes into 28 how many times? 7. So now you can divide so that you get a solution for y, which is your ultimate goal. Make sure you include the minus sign in there, because you really want to know what y is, not -y.


Your solution is -7=y


I hope this answered your question. Email me at [email protected] if you'd like any more help with anything. I'm an engineer and math is my strong suit, so feel free to ask!!


[img]smileys/smilies_01.gif[/img] Josie

[kentuckygalrk]

yeah.... that's right... It's been a while for me!


And then the solution to 'c' is actually


C.) 9(y + 2) = 3(y - 2)



9y + 18 = 3y + 6


9y = 3y - 12


6y = -12


y = -3


Edited by: kentuckygalrk

[Jenneh]

i just remember being told that both sides had to be treated equally. and u needed to get all numbers on ONE side of the equals sign.


so if i do A.) -7x - 24 = -129 (to get all the numbers on one side of the equals sign you hav to + 129 to the right hand side, so that it turns to 0 -- which means you need to plus 129 to the left hand side.


= -7x -105 ....


B.) 3(2y - 3) = 27 (you need to get rid of the brackets first. by doing what was explained above)


= 6y -9 = 27 (then you need to minus 27 from the right hand side to make it zero, and this means you have to minus 27 from the LEFT hand side to make it equal)


= 6y -36 ...


C.) iv done..


D.) 8y + 4 + 18 = 4y - 6 ( ummm hard one) ((first you need to minus 4y from the right hand side -- and minus 4y from the left hand side))


= 4y + 4 + 18 = -6 (then you need to PLUS six to the right hand side -- therefore plus 6 to the left hand side)


= 4y + 4 + 18 + 6


= 4y +28


dont quote me on these... i hvent done maths since GCSE so i may have slipped up somewhere along the way!!


Jen xxxxxxx

[Jenneh]

ok --- me and kentuckygrl are doing 2 different things...


are u trying to plot a line graph or are you solving what x / y is?? theres a big difference =|


god i bet iv confused u now. ignore me lol.


xxxx

[mystikal star]

LOL. I'm a little confused but there are more than one technique to doing these things right? I checked my answers with yours and they are right. I'm still a little lost but hopefully with more practice I'll get better. Does anyone know where I can find practice things on these darn things?


I appreciate all the help by the way. Thanks SO much.

[Jenneh]

do you have a mths textbook or smthing? shud be exercises in there u can do, surely?


im worried now cos i dont want to have said it wrong.. u say ur answers are the sme as mine... but kentuckygrl is doing smthing which i was ALSO taught but comes up with a completly differnet answer....


maybe if i ask exactly what the exercise says to do?? or does it not?


xxx

[HDogg]

Holy crap! I never thought I'd have to look at another algebra problem in my life! I will now get the heck out of this topic before I am forced to hurt somebody.


***Runs away screaming at the top of my lungs***


[img]smileys/smilies_10.gif[/img][img]smileys/smilies_10.gif[/img][img]smileys/smilies_10.gif[/img][img]smileys/smilies_10.gif[/img][img]smileys/smilies_10.gif[/img][img]smileys/smilies_10.gif[/img]

[kentuckygalrk]

okay... this post was incorrect... sorry Jenneh! Edited by: kentuckygalrk

[mystikal star]

Solve for the variable? Whats that mean? I'm dumb.

[kentuckygalrk]

no... you're not dumb... that stuff wasn't easy for me when I first started learning it, but thankfully I had a wonderful math teacher and it's relatively simple now. Hopefully it will be for you too!


Now... as for solving for the variable... that was probably the wrong word to use... basically I just wanted to know if you are supposed to figure out what the y and the x equal as I did in the problem... or simply breakdown the problem like Jenneh did.


~Rachel

[Jenneh]

what the hell --- you need to DIVIDE instead of SUBTRACTING??


ok, well i think im jut gnna get confused myself here -- and considering i work with little kids teaching them maths -- i do NOT want to do that. lol.


i'll leave this up to you [img]smileys/smilies_02.gif[/img]


Jen xxxx

[mystikal star]

I needed to find out what the variable. Kentuckygalrk or 2jo2- Is it okay if I email you sometime for help? I'm understanding this now but now I got another lesson that I'm lost on. This sucks. Why couldnt I have been a math genius!!!

[kentuckygalrk]

Aight... my dumb brain blanked yesterday and I just wanted to say that Jenneh, I'm sorry becauseyou were in fact right with the subtracting of the 4y from both sides. I was confused on the whole multiplication thing! See... it's been awhile I so I needed a little refresher Imaking the problemsmore complicated than they are!


So then that makes the answer to that previous problem


8y + 4 + 18 = 4y - 6
8y + 22 = 4y - 6
8y = 4y -28
8y - 4y = -28
4y = -28
y = -7



TADA! Lol... now I KNOW that's right ;o)
And now that I know what I'm doing mystical star you are more than welcome to email me any of your questions/problems and I will be glad to help you figure them out. If I can't, I have a brother who's a math wiz and I'm sure he'll help me help you! LOL My email addy is [email protected] I work today so it might be a while before I get back to you... but I definitely will at some point today!


~Rachel

[2jo2]

You can email me anytime too, and I'll help you out, I love algebra so I think it's fun to help. The variable is the thing you're solving for like x or y. They call it a variable because the value varies. You can make x or y be anything you want, just in that particular equation (letter D) y = -7. If you have some other examples that you're stuck on I'd be glad to help you.


[email protected]


Good luck!!

[mystikal star]

After some help from my brother I'm finally understanding the equations!!! Heck yeah. But now I'm on to something even harder.....


<SUP>a) -1</SUP>/<SUB>4</SUB>x = <SUP>3</SUP>/<SUB>22</SUB>


b) <SUP>31</SUP>/<SUB>30</SUB> = x + <SUP>5</SUP>/<SUB>6</SUB>


How the heck do you do that? And where the heck to begin? I should stop posting this stuff. I feel like I'm cluttering the board. Sorry.

[2jo2]

You have to find the common denominator of the fractions first:


a.)


-1/4x = 3/22


-11/44x = 6/44


then you divide 6/44 by -11/44 to find the value of x.


remember when you divide fractions, you invert the divisor and multiply them together.


x = (6/44)* (-44/11)


x = -6/11Edited by: 2jo2

[Melikasa]

I love math I wish I would have seen this post a while back. It is nice to see so many people that can help out with it for you.

[kentuckygalrk]

And then B would be


31/30 = x + 5/6 (5/6 changes to 25/30 for common denominator)
31/30 - 25/30 = x
6/30 = x (make sure you simplify as much as you can to, 6/30 = 1/5)
1/5 = x


I think these are acutally the more tricky part because as 2jo2 said you have to remember that when you divide and multiply you have to invert the second and then cancel and all that fun stuff. Again... if you've got any questions I'm sure one of us can help u out.


~Rachel

[mystikal star]

Okay. I think I got it. So I started a few on my own. Can you tell me if my answers are correct?


Oh and I'm using "/" for a fraction bar.


a.) 7/12 = m + 12


I got 1.


b.) b + 9.2 = 6.8


I got -16.


c.) 3/8m - 5 = 7/8m


I got -10.


So just how wrong am I?


And also, this problem I can't figure outAT ALL.


3/4x + 3 = x + 1/2.


And I hope I'm not driving you all insane and wasting space on the board. I feel bad for bugging everyone. This is basically baby math and I can't understand it. Me dumb.Edited by: mystikal star

[2jo2]

ok...


I did them and I'll show you how.


a.) 7/12 = m +12


change 12 into a fraction so you can manipulate it with the other fraction.


12 = 144/12, these are the same thing because you're multiplying the original number, 12 by the value of 1 (or 12/12) and it doesn't change the overall equation, so you can just substitute it back into the original equation.


7/12 = m + 144/12


next solve for m by getting the fractions on the other side of the =.


7/12 - 144/12 = m


-137/12 = m


remember you can always check your work by putting your answer back into the original equation to see if it works, if both sides equal the same thing.


b.) b +9.2 = 6.8


this one has just plain old numbers so you can just get the b on one side of the = and the numbers on the other side. use a calculator to do the math.


b = 6.8-9.2


b = -2.4


c. ) you did this one right!


d.) 3/4x + 3 = x + 1/2


change the non-fraction numbers into fractions first so you can add/subtract easier. put the 3 into a fraction so it's easily manipulated with the 1/2, so you have to find the common denominator. change 3 into 6/2. next turn the plain x into 4ths, so you can easily add/subtract with the 3/4x. turn the x into 4/4x. since you're multiplying by essentially 1 (4/4 = 1) it doesn't change the overall value of the equation.


so let's put those in there:


3/4x + 6/2 = 4/4x + 1/2


next put the x's together and the numbers together:


6/2 - 1/2 = 4/4x - 3/4x


and now you can just subtract each side and solve it:


5/2 = 1/4x


next divide 5/2 by 1/4 to solve for x, remember to invert and multiply:


5/2 * 4/1 = x


x = 20/2 = 10


I'm at work right now, but please feel free to email me at work if you need any help... [email protected] and I'll be glad to help you out. remember to check your answer by putting it in place of the variable (x,y,b,m, whatever you've got) and it'll tell you if you're right or not. Good luck!