SOLUTION: 1) if 8^x=4, what does 8^-3x equal? 2) 2^(7-3x)=1/4, x=? 3) 4^(3x-7)=16, x=? 4) 9^2x * 27^(3-x)=1/9, x=? 5) log3^9=x

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: 1) if 8^x=4, what does 8^-3x equal? 2) 2^(7-3x)=1/4, x=? 3) 4^(3x-7)=16, x=? 4) 9^2x * 27^(3-x)=1/9, x=? 5) log3^9=x      Log On


   

Question 943359: 1) if 8^x=4, what does 8^-3x equal?
2) 2^(7-3x)=1/4, x=?
3) 4^(3x-7)=16, x=?
4) 9^2x * 27^(3-x)=1/9, x=?
5) log3^9=x
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
1) if 8^x=4, what does 8^-3x equal?
8%5Ex=4
1%2F8%5Ex=1%2F4
cube both sides
1%2F8%5E%283x%29=1%2F4%5E3
8%5E%28-3x%29=1%2F64
..
2) 2%5E%287-3x%29=1%2F4, x=?
2%5E%287-3x%29=2%5E-2
7-3x=-2
3x=9
x=3
..
3) 4%5E%283x-7%29=16, x=?
4%5E%283x-7%29=4%5E2
3x-7=2
3x=9
x=3
..
4) 9%5E2x+%2A+27%5E%283-x%29=1%2F9, x=?
3%5E2%5E2x+%2A+3%5E3%5E%283-x%29=1%2F3%5E2
3%5E4x+%2A+3%5E%289-3x%29=3%5E-2
3%5E%289%2Bx%29=3%5E-2
9+x=-2
x=-11
..
5) log(3^9)=x
10^x=3^9
xlog10=log(3^9)
x=log(3^9)