If 2^x=7, what is the value of 2^2x?

Log 2^x = log 7

x log 2 = log 7

x = log7/log2 = 2.8074

2^(2x) = 2^(2*2.8074) = 49

Thanks, EP....here's a slightly easier way

2^x  = 7

2^(2x) =

 [ 2 ^x ] ^2  =

7^2   =

49