SOLUTION: Solve the equation. 15^x=5^(x+2)

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Question 371060: Solve the equation. 15^x=5^(x+2)
Found 2 solutions by robertb, Edwin McCravy:
Answer by robertb(5830)   (Show Source): You can put this solution on YOUR website!
take logs of both sides:
x*log15 = (x+2)*log5,
xlog15 = xlog5 + 2log5,
xlog15- xlog5 = 2log5,
x(log15-log5) = 2log5,
xlog(15/5) = 2log5,
xlog3 = 2log5,
x = 2log5/log3.
Answer by Edwin McCravy(20055)   (Show Source): You can put this solution on YOUR website!

Take logs of both sides







Get both terms that contain x alone on the left.



Factor out x



Divide both sides by that big parentheses:



You can get the numerical approximation from that 
or you can simplify some more.







Edwin
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