4^n = 1/64 What value of n solves the equation?  not only the answer ... how do I work it?

[latex]4^n = \frac{1}{64}\\ \\4^n =(\frac{64}{1})^{-1}\\ \\4^n =64^{-1}\\ \\4^n =(4^3)^{-1}\\ \\4^n =4^{3*(-1)}\\ \\4^n =4^{-3}\\ \\n=-3[/latex]