need a bit of help on this sine problem

[corsec]

I have the equation 4sin((x/5)- pi) + 2 for a sine wave

what I want is to be able to find a way to distribute out something and put it outside the parenthesis but I'm not sure which would be the best thing.
I'm trying to find the period also on it

the form is supposed to be f(x) = A sin(B(Theta - h)) + k

so I've gotten 4 sin(x/5)(1- pi)) + 2 but it doesn't jive with the answers I'm given

formula for the period is

(2pi)/b

the closest answer is (2pi)/5 but i'm not sure why. guess my distributing skills are rusty.

 

[Gene]

You have
4sin((x/5)- pi) + 2
You want
f(x) = A sin(B(Theta - h)) + k
x will be theta so you want
f(x) = A sin(B(x - h)) + k
Look at what you need to factor out to get x by itself. Don't forget to factor the same thing out of pi then you have it. What you factor will be B. h will be pi/B. You already have A and k.