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| Question 427704:  The exercise asks to solve algebraically this equation: 36(1.35)^x=4.35 My work comes up as: 36(1.35)^x-4.35=0 However, I have a key: approx. 8.024 Obviously, my work is wrong, and I wonder if I have to solve it using log but I am not sure about the steps. Can you help me to do it, please? Thank you
 Answer by lwsshak3(11628)
      (Show Source): 
You can put this solution on YOUR website! The exercise asks to solve algebraically this equation: 36(1.35)^x=4.35 My work comes up as: 36(1.35)^x-4.35=0 However, I have a key: approx. 8.024 Obviously, my work is wrong, and I wonder if I have to solve it using log but I am not sure about the steps. ..
 Usually, when you need to solve a variable that is an exponent, logarithms are required.
 36(1.35)^x=4.35
 (1.35)^x=4.35/36
 taking logs of both sides using the exponent  and division rules of logarithms.
 xlog(1.35)=log(4.35)-log(36)
 x=[log(4.35)-log(36)]/log(1.35)
 using calculator
 x=-7.0420..
 ..
 Check:
 36*1.35^-7.042=4.35
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