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prettyybabyy
Oct 1, 2007, 04:04 PM
I need help with some algebra I just don't get.


3(5x-4) = 8x + 2


I just need someone to explain the basics.
I can figure out if someone would tell me how to do it.

Wondergirl
Oct 1, 2007, 04:28 PM
This has been copied down incorrectly. No algebra problem has two equal signs.

KISS
Oct 1, 2007, 05:36 PM
The first = sign is probably a "+".

Wondergirl
Oct 1, 2007, 05:54 PM
The first = could be a + or -, or the second = could be a + or -.

MOWERMAN2468
Oct 1, 2007, 06:09 PM
The first = could be a + or -, or the second = could be a + or -.
You betcha it could be, but IF , you guess wrong it will be the wrong answer, correct? Yes.

Wondergirl
Oct 1, 2007, 06:11 PM
That's why I'm not guessing.

Maybe it's algebra for the 21st century...

KISS
Oct 1, 2007, 09:04 PM
MM/WG:

What key is above the "=" sign?
Ok, either "=" could be a "+"

But I'll bet dollars to donuts that someone didn't hold the shift key down long enough.

rebel-2
Oct 2, 2007, 08:41 AM
3(5x-4) = 8x = 2

Hello there, I believe you have written the question wrong.

IF the equation was 3(5x-4)+8x=2
first step

since the there is a "3" before the bracket you multiply the content of the brackets by 3.

Therefore it will be
15x-12+8x=2
15x+8x=2+12 (rearrange the like terms "x" and simplify. Take "-12" to the other side and it becomes "+12")

23x=14
x=14/23

prettyybabyy
Oct 2, 2007, 02:12 PM
I need help with some algebra i just don't get.


3(5x-4) = 8x + 2


i just need someone to explain the basics.
i can figure out if someone would tell me how to do it.
Yeahh uhm sorry I didn't hold the shift keyy down.
Stupid me.
Shesh!
No wonder I can't get it right.

Wondergirl
Oct 2, 2007, 02:20 PM
3(5x-4) = 8x + 2

Multiply the numbers inside the parens by the 3. Move the x numbers to one side of the =, and the numbers without x to the other side of the =. Add or subtract as needed. Divide both sides by the same number to get x.

I have it figured out. The answer is...

(And I never thought I would ever use high school algebra. Woo woo!! )

prettyybabyy
Oct 2, 2007, 02:37 PM
Thanks a bunches.
More help then my teacher gives :]]

Wondergirl
Oct 2, 2007, 02:43 PM
So what is the answer? (I'm sure the teacher explained how to move stuff onto either side of the = and then how to reduce for an answer... )

rebel-2
Oct 3, 2007, 04:28 AM
Yeahh uhm sorry i didn't hold the shift keyy down.
stupid me.
shesh!!
no wonder i can't get it right.
ah lol so its "3(5x-4) = 8x + 2" and not "3(5x-4)+8x = 2"

3(5x-4)=8x+2
15x-12=8x+2
15x-8x=12+2
7x=14
x=14/7
x=2

tcheer123
Oct 15, 2007, 12:05 PM
3(5x-4) = 8x + 2
To answer this, you would first distribute the 3.
15x-12=8x+2
Then after that, you would combine like terms.
7x=14
Then you would divide both sides by 7.
x=2.

chancelord
Jun 23, 2008, 07:05 PM
OK, lets start. According to the combining like terms rule, the first thing yo must do is to eliminate the parenthesis by multiplying the numbers outside the parenthesis with the number inside it so if you got 3(5x-4)=8x+2 then you multiply 3 by every single number onside the parenthesis and you get 15x-12=8x+2, now still going with the combine like terms theorem you must pass all x variables to the left and all number to the right and you will get -14=-7x then because now you have all to its determined side you must divide both sides by -7 and you will get 2=x then you just invert it and you will get x=2 because the correct way of writing it x must go first. If you have any problem still just ask, but this is all the answer to the question.

travisr119
Jun 29, 2008, 12:54 PM
I need help with some algebra i just don't get.


3(5x-4) = 8x + 2


i just need someone to explain the basics.
i can figure out if someone would tell me how to do it.
all your doing is solvin for "x"
its 3(5x-4) = 8x+2
15x-4 = 8x+2
+4____+4
15x = 8x+6
-8x -8x
7x = 6
______
7 7
x = 6/7

travisr119
Jun 29, 2008, 01:47 PM
actually I think IT IS possible to have two = signs!!
They have them in complicated problems =P

MaGiC_DaN90
Jul 31, 2008, 08:40 PM
wait, wouldn't 3(5x-4) simplify as 15x-12??
this is confusing...

KISS
Aug 1, 2008, 06:20 AM
Simplify? No; Equivalent expression? Yes

15x - 12 = (3*5)x+(3*4); 15 = 3*5; 12= 3*4

Esentially doing prime factorization of both sides. 3 is common to both sides or you can divide both sides by 3.

Thus 5x+4;

Note that if you substitute x=1; just for fun
3(5*1-4)=15*1-12
3(5*-3) )= 15*-12

15*-12=15*-12

Same answer.

sammie62
Aug 25, 2008, 05:42 PM
How to solve equation 3Z+U=12