Question 487350: I would like to know how to solve for x using logarithms for this equation :
4*3^x = 7*5^x
Thank you so much for your time. Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! 4*3^x = 7*5^x
take log of both sides
log4+xlog3=log7+xlog5
xlog3-xlog5=log7-log4
x(log3-log5)=log7-log4
x=(log7-log4)/(log3-log5)
using calculator
x=.2430/-.2218=-1.0955
Check:
4*3^x=4*3^-1.0955=1.2005
7*5^x=7*5^-1.0955=1.2005
(