(2^2x-1)+(2^2x-2)=48

2^(2x-1) + 2^(2x-2) = 48
(2^(2x))/2 + (2^(2x))/4 = 48
2*2^(2x) + 2^(2x) = 192
2^(2x) = 64
x = log2(64)/2
x = 3