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

#### fiskonian

##### New member
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.

#### Subhotosh Khan

##### Super Moderator
Staff member
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.
Show your work - we can find the problem.

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

#### stapel

##### Super Moderator
Staff member
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!

Eliz.

P.S. Welcome to FreeMathHelp!

#### fiskonian

##### New member
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

##### Super Moderator
Staff member
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

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

#### Mrspi

##### Senior Member
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

##### New member
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

##### Senior Member
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 :?: