Sine Problem

1. The problem statement, all variables and given/known data
The half-wave design may be represented as a portion of a sine function. Determine a sine function that models the half wave design, assuming that the origin is at the point (0,0). Express in the form [tex]y=asin(b(x-c))+d[/tex]

http://img231.imageshack.us/img231/3549/archpc5.jpg [Broken]​

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2. Relevant equations
[tex]y=asin(b(x-c))+d[/tex]


3. The attempt at a solution
My answer is [tex]y=4sin(\frac{\pi}{10}(x+5))+7[/tex]

Am I right? I was just confused when the question said to represent it as a portion of a sine function.

 

Thanks. I forgot to write it down, but the question already provides the domain of x between -5 and 5.