I am currently doing a project in mechanical engineering consisting in finding the equation of the catenary section of the Golden Gate Bridge.

I am currently doing a project in mechanical engineering consisting in finding the equation of the catenary section of the Golden Gate Bridge. I am trying to find the hyperbolic equation in the form y=Ccosh(x-a)/c +b that passes through the following points (640, 227), (-640, 227) and (0,0). I was not able to find the equation. Can someone please tell me what the equation is? what are the values of a, c, and b ?

Thanks