SOLUTION: 3^(x+1)*9^-x=27

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: 3^(x+1)*9^-x=27      Log On


   

Question 1002689: 3^(x+1)*9^-x=27
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
3%5E%28x%2B1%29%2A9%5E%28-x%29=27

3%5E%28x%2B1%29%2A%283%5E2%29%5E%28-x%29=27

3%5E%28x%2B1%29%2A3%5E%282%28-x%29%29=27

3%5E%28x%2B1%29%2A3%5E%28-2x%29=27

3%5E%28x%2B1-2x%29=3%5E3

3%5E%281-x%29=3%5E3
The bases are equal, both being 3. The exponents must also be equal.

1-x=3
-x=3-1
x=1-3
highlight%28x=-2%29