



 
Hi Dave, You took the log of both sides to get
but log(2^{x} + 12) is not equal to log(2^{x}) + log(12). What is true is that log(2^{x} × 12) = log(2^{x}) + log(12) but that's no help here. I think your first solution is best "It's obvious the answer is 2" but another method is to use the fact that 4 = 2^{2} and use the laws of exponents to see that 4^{x} = (2^{2})^{x} = 2^{2x} = (2^{x})^{2}. Thus
Can you complete the solutiion? If you need more help write back,  


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