SOLUTION: I am coming up with an answer but its from plugging it in a calculator, how do I work this backwards? I am coming up with x=1.82 Approximate answer: 3*5^(2-x)=4

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: I am coming up with an answer but its from plugging it in a calculator, how do I work this backwards? I am coming up with x=1.82 Approximate answer: 3*5^(2-x)=4      Log On


   



Question 674831: I am coming up with an answer but its from plugging it in a calculator, how do I work this backwards? I am coming up with x=1.82
Approximate answer:
3*5^(2-x)=4

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
3*5^(2-x)=4
;
divide both sides by 3
5^(2-x) = 4/3
:
using logs
log(5^(2-x)) = log(4/3)
:
log equiv of exponents
(2-x)*log(5) = log(4/3)
.69897(2-x) = .1249
2 - x = .1249%2F.69897
2 - x = .1787
2 - .1787 = x
1.82 = x