Respuesta :
Answer:
[tex] {4}^{x - 1} = \frac{49}{4} [/tex]
Step-by-step explanation:
My work is in the attachment but I essentially used a hefty bit of Algebraic manipulation to turn 2^x into 4^(x-1) and then isolating that bit.
Comment if you have any questions.

Answer:
49/4
Step-by-step explanation:
4^x-1 = (2^x)^2/4 = 7^2/4 = 49/4