Question

Solve 3^x−5 = 9. (3 points) Select one: a. x = −3 b. x = 2 c. x = 7 d. x = 8

Answer 1

ANSWER

C. x=7

EXPLANATION

The given exponential equation is

${3}^{x - 5} = 9$

We rewrite the right hand side as 3 raised to exponent 2.

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

Observe that the base of both sides of the equation are equal.

We now equate the exponents.

$x - 5 = 2$

Solve for x,

$x = 2 + 5$

$x = 7$

The correct choice is C.