How do you solve 9^(x+1) = 27?

2 Answers
Apr 12, 2016

x = 1/2

Explanation:

We will use the following properties:

  • log(a^x) = xlog(a)

  • log_a(a^x) = x

9^(x+1) = 27

=> log_3(9^(x+1)) = log_3(27)

=>(x+1)log_3(9) = log_3(27)

=>(x+1)log_3(3^2) = log_3(3^3)

=>2(x+1) = 3

=>x+1 = 3/2

:. x = 1/2

Apr 12, 2016

Alternative solution:

Explanation:

You can write everything in the same base:

(3^2)^(x + 1) = 3^3

3^(2x + 2) = 3^3

3^(2x) = 3^(3 - 2)

3^(2x) = 3^1

2x = 1

x = 1/2

Hopefully this helps!