http://i31.tinypic.com/2qcp7r6.png

There is no answer in my textbook for this question.

Please show a step by step solution so I could follow through...

Here's what I've done so far:

$\displaystyle y' = \frac {5(x + 2) - 1(5x + 2)}{(x+2)^2}$

$\displaystyle y' = \frac {5x + 10 - 5x - 2}{(x+2)^2}$

$\displaystyle y' = \frac {8}{(x+2)^2}$

Now what?