SOLUTION: solve 7^(6-x) * 5^(4-x) =3

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Question 1084348: solve 7^(6-x) * 5^(4-x) =3
Answer by ikleyn(52864) About Me  (Show Source):
You can put this solution on YOUR website!
.
Take log base 10 of both sides. You will get


    %286-x%29%2Alog%2810%2C%287%29%29+%2B+%284-x%29%2Alog%2810%2C%285%29%29 = log%2810%2C%283%29%29,   or

     = log%2810%2C%283%29%29,   or

    6%2Alog%2810%2C%287%29%29+%2B+4%2Alog%2810%2C%285%29%29+-+log%2810%2C%283%29%29 = x%2A%28log%2810%2C%287%29%29+%2B+log%2810%2C%285%29%29%29.


Hence,  x = .

Now use your calculator.


On logarithms and their properties, see the lessons
    - WHAT IS the logarithm
    - Properties of the logarithm
    - Change of Base Formula for logarithms
    - Solving logarithmic equations
    - Using logarithms to solve real world problems
in this site.

Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic "Logarithms".