Question

to solve the equation $2^{x - 1}-7 = 9$, first
1 add 7 to each side
what common base can be used to rewrite each side of the resulting equation?
2
32
16
4

Explanation:

Step1: Apply first given operation

$2^{x-1} - 7 + 7 = 9 + 7$
$2^{x-1} = 16$

Step2: Rewrite right-hand side

$16 = 2^4$, so the equation becomes $2^{x-1} = 2^4$

Answer:

2