In addition to x=8, im supposed to get x=-2. how do I get this answer?

Given the function f(x) = log base 4(x+8) , find the value of f^-1(2)

Can someone me out here and the tell me the greatest common factor

Val and tony get paid per project. val is paid a project fee of $44 plus $12 per hour. tony is paid a project fee of $35 plus $15 per hour. write an expression to represent how much a company will pay to hire both to work the same number of hours on a project.