# Thread: Evaluate and simplify f(b/3)

1. ## Evaluate and simplify f(b/3)

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2. ## Re: Evaluate and simplify f(b/3)

Originally Posted by Eraser147
Click image to enlarge.
Hi Eraser147!

As a first step, can you replace each occurrence of x by (b/3)?

3. ## Re: Evaluate and simplify f(b/3)

I don't know how to use the codes in the forum but it will look like this: b/3 + 8 over b^2/9 +2

4. ## Re: Evaluate and simplify f(b/3)

Originally Posted by Eraser147
I don't know how to use the codes in the forum but it will look like this: b/3 + 8 over b^2/9 +2

[TEX]\frac{\frac{b}{3}+8}{\frac{b^2}{9}+2}[/TEX] gives $\displaystyle \frac{\frac{b}{3}+8}{\frac{b^2}{9}+2}$

^ Thankyou.

6. ## Re: Evaluate and simplify f(b/3)

I see my problem now. I didn't multiply both sides the denominator of both the equation's numerator and demoninator.

7. ## Re: Evaluate and simplify f(b/3)

Good!

Originally Posted by Eraser147
I see my problem now. I didn't multiply both sides the denominator of both the equation's numerator and demoninator.
Uhh... so with what number are you multiplying both numerator and denominator?

8. ## Re: Evaluate and simplify f(b/3)

$\displaystyle \frac{\frac{b}{3}+8}{\frac{b^2}{9}+2}$ multiply 3 both top and bottom, and 9 both top and bottom.

9. ## Re: Evaluate and simplify f(b/3)

Lastly, I simplify from $\displaystyle {\frac{9b+216}{\frac{3b^2}{1}+54}$ which equates to $\displaystyle {\frac{3b+72}{\frac{b^2}{1}+18}$

10. ## Re: Evaluate and simplify f(b/3)

Originally Posted by Eraser147
Lastly, I simplify from $\displaystyle {\frac{9b+216}{\frac{3b^2}{1}+54}$ which equates to $\displaystyle {\frac{3b+72}{\frac{b^2}{1}+18}$
It should be $\displaystyle \frac{\frac{b}{3}+8}{\frac{b^2}{9}+2}=\frac{3b+72} {b^2+18}$

11. ## Re: Evaluate and simplify f(b/3)

You've got it!!