Question

Resolva $\left[\begin{array}{ccc}2^{x+1}&2^{x}&\\4&3&\7\end{array}\right]$ = 16

Answer 1

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$3.2^{x+1}-4.2^x=16 \\ \\ 3.2^x.2-4.2^x=16 \\ \\ 2^x(6-4)=16 \\ \\ 2^x(2)=16 \\ \\ 2^x=16\div2 \\ \\ 2^x=8 \\ \\ 2^x=2^3 \\ \\ x=3$