SOLUTION: log_4 (4) + log_6 (7x)+1=4 Find x Thanks

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Question 1000307: log_4 (4) + log_6 (7x)+1=4
Find x
Thanks
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

if you have
log%284%2C+%284%29%29+%2B+log%286%2C+%287x%29%29%2B1=4, then
log%28+%284%29%29%2Flog%284%29+%2B+log%28%287x%29%29%2Flog%286%29=4-1

1+%2B+log%28%287x%29%29%2Flog%286%29=3
log%286%29+%2B+log%28%287x%29%29=3log%286%29
log%286%287x%29%29=log%286%5E3%29....if log same, than
6%287x%29=6%5E3
42x=216
x=216%2F42
x=36%2F7=> exact solution
x=5.14-> approximate solution