Question

How do you solve 2^(x+2)-2^x=8

Answer 1

2^(x+2) = 2^x * 2^2 = 4*2^x

So you have
2^(x+2)-2^x=8
4*2^x - 2^x = 8
3*2^x = 8
2^x = 8/3
x = log(8/3) / log2