SOLUTION: Had trouble with a few problems similar to this one.. Solve: 5^(x+2)= 4^(l-x)

Algebra ->  Test -> SOLUTION: Had trouble with a few problems similar to this one.. Solve: 5^(x+2)= 4^(l-x)      Log On


   

Question 242325: Had trouble with a few problems similar to this one..
Solve: 5^(x+2)= 4^(l-x)
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve
5%5E%28x%2B2%29 = 4%5E%28l-x%29
Use logs
log%285%5E%28x%2B2%29%29 = log%284%5E%28l-x%29%29
log equiv of exponents
%28x%2B2%29%2Alog%285%29 = %281-x%29%2Alog%284%29
Find the logs
.69897(x+2) = .60206(1-x)
:
.69897x + 1.39794 = .602061 - .60206x
:
.69897x + .60206x = .602061 - 1.39794
:
1.30103x = -.79588
:
x = %28-.79588%29%2F1.30103
x = -.61173
:
:
Check solution on calc:
enter 5^(-.61173+2) = 9.34
enter 4^(1-(-.61173)) = 9.34; confirms our solution