Deriving an Input Value in an Algebra Formula

I'm working out an algebra problem and am wondering if it is possible to isolate the "Input" value below:

Input / (Input + Constant A) = Constant B

I've tried adjusting it, but have only gotten to:

Input - (Input * Constant B) = (Constant A * Constant B)

I can't seem to get the "input" value by itself, and I am wondering if it is even possible?

Thanks for your help