If $2^8=4^x$, what is the value of $x$?
I notice that both 2 and 4 are powers of 2, so I can rewrite the equation using the same base on both sides. Using the exponent rules, I get $2^8=(2^2)^x=2^{2x}$. Now, since the bases are equal, the exponents must also be equal, so I can set up a simple equation: $8=2x$. Solving for $x$, I get $x=\frac{8}{2}=4$. 