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Simplifying help!

Hi, I'm doing a paper & I cant figure out how this:

1/5[1/3 - 1/(5n+3)]

simplifies to this:

n/(3(5n+3)

Thanks so much!
1315n+3=(5n+3)33(5n+3)=5n3(5n+3)\frac{1}{3} - \frac{1}{5n+3} = \frac{(5n+3)-3}{3(5n+3)} = \frac{5n}{3(5n+3)}

Now take 1/5 of it.
1/3 - 1/5n+3
Our class does this thing called 'tepee', where you times both bottoms together, the bottom left with the top right, and the bottom right with the top left, named the tepee because when you draw the lines on they look like a tepee.
this means that you do:
3 X (-1)= -3 (the one is negative as you are taking away the fractions, don't forget this!)
(5n+3) X 1= 5n +3
3 X (5n+3)= 15n+9
This leaves you with (5n+3-3)/(15n+9)
Simplified makes 5n/(15n+9)
Then you divide by 5
The 5n/5= n
the 15n=3n
the 9 leaves you with 1.8
This overall makes n/(3n+1.8)
Hope this helps :biggrin:

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