need help with 1/9(x+18)+1/3(2x+3)=x+3

fiskonian

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Sep 12, 2007
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I need help with this problem.
1/9(x+18)+1/3(2x+3)=x+3
I know the answer is 0 because i looked in the back of the book to check my work.
However i cannot seem to work it out to get 0. please help me.
 

Subhotosh Khan

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fiskonian said:
I need help with this problem.
1/9(x+18)+1/3(2x+3)=x+3
I know the answer is 0 because i looked in the back of the book to check my work.
However i cannot seem to work it out to get 0. please help me.
Show your work - we can find the problem.

By the way, the answer in the book is correct.
 

stapel

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fiskonian said:
I need help with this problem.
1/9(x+18)+1/3(2x+3)=x+3
Working backwards from the answer, I think you mean:

. . . . .(1/9)(x + 18) + (1/3)(2x + 3) = x + 3

After you multiplied through by the common denominator, and simplified the parenthetical stuff, what did you do next? Please reply showing all of your steps.

Thank you! :D

Eliz.

P.S. Welcome to FreeMathHelp! 8-)
 

fiskonian

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ok.
1/9(x+18)+1/3(2x+3)=x+3
9(1/9[x+18]+1/3[2x+3]=x+3)
x+18+6x+9=x+27
7x+27=x+27 (once i got to here i knew the answer... finding out how to get to there was what i had problems with.)
6x=0
x=0
im not sure if this is followable, its hard to show my work on this. PS- ill probably be on here alot these next few years :)
 

stapel

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fiskonian said:
1/9(x+18)+1/3(2x+3)=x+3
9(1/9[x+18]+1/3[2x+3]=x+3)
x+18+6x+9=x+27
Hint: 9(x) does not equal x. :wink:

Eliz.
 

fiskonian

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9(1/9[x...
9 divided by 9 = 1, 1x1 =1x right?
 

Mrspi

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fiskonian said:
ok.
1/9(x+18)+1/3(2x+3)=x+3
9(1/9[x+18]+1/3[2x+3]=x+3)
x+18+6x+9=x+27
7x+27=x+27 (once i got to here i knew the answer... finding out how to get to there was what i had problems with.)
6x=0
x=0
im not sure if this is followable, its hard to show my work on this. PS- ill probably be on here alot these next few years :)
The common denominator for the fractions is 9. Multiply both sides of the equation by 9:

9*(1/9)(x + 18) + 9*(1/3)(2x + 3) = 9*(x + 3) <======here's where your mistake is!!

1(x + 18*) + 3(2x + 3) = 9(x + 3)

x + 18 + 6x + 9 = 9x + 27

Ok...now see what this gives you!
 

fiskonian

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wow... i see how i messed up now but it didnt effect my answer at all cause either way it wouldve been 0. thanks! and im sorry i troubled you with a simple mistake.
 

Denis

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1/9(x+18)+1/3(2x+3)=x+3

First of all, that should be shown this way: (x + 18) / 9 + (2x + 3) / 3 = x + 3

Then the multiplication by 9 affects EACH of the terms:
9 * (x + 18) / 9 = x + 18
9 * (2x + 3) / 3 = 3(2x + 3) = 6x + 9
9 * (x + 3) = 9x + 27

Kapish :?:
 
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