Hi I need help with this problem...I cant figure it out...help would be appreciated! (Trying to find x)
$\displaystyle \frac{\ 10^8}{10^5} = \frac{\ x}{10^9} $
Do you know your power rules?
You need the rules:
$\displaystyle \frac{10^m}{10^n}=10^{m-n},$
$\displaystyle 10^m\cdot 10^n = 10^{m+n}.$
So for example, in your setup, we have
$\displaystyle \frac{10^8}{10^5}=10^{8-5}=10^3.$
And you could multiply both sides of the equation by $\displaystyle 10^9$ to get rid of that in the denominator on the right hand side.
Hope this gives you a clue. Otherwise, feel free to ask about troublesome parts.