Question

Solve 3^^^x−5 = 9.
A. x = −3
B.x = 2
C. x = 7
D. x = 8

Answer 1

Answer:

x=7

Step-by-step explanation:

3^(x-5)=9

3^(x-5)=3^2

x-5=2

x=7

Answer 2

For this case we must solve the following equation:

$3^{x-5} = 9$

We rewrite:

$9 = 3 ^ 2 = 3 * 3$

Then, replacing:

$3^{x-5} = 3 ^ 2$

For the bases to be equal then it must be fulfilled that:

$x-5 = 2$

Adding 5 to both sides of the equation:

$x-5 + 5 = 2 + 5\\x = 7$

Answer:

$x = 7$

Option C