# Math Help - algebraic fraction question

1. ## algebraic fraction question

hi

can anyone clear my mind

Q. 1/3x -2/x+3

I understand tha I have to make both denominators the same and to do this I multiply them together.

I make the answer to be 3x^2+3 and would use this as the denominator, but the answer in my book tells me that the denomonator should be 3(x+3)
am I missing something?

Dave

2. ## Re: algebraic fraction question

$\frac{1}{3} \cdot x -\frac{2}{x+3}=\frac {x(x+3)-6}{3(x+3)}$

3. ## Re: algebraic fraction question

why do I write 3(x+3)

4. ## Re: algebraic fraction question

Originally Posted by davellew69
why do I write 3(x+3)
$\frac{a}{b}+\frac{c}{d}=\frac{a \cdot d+b \cdot c}{b \cdot d}$

5. ## Re: algebraic fraction question

Originally Posted by davellew69
1/3x -2/x+3
Brackets required: x/3 - 2(x+3)