How do you solve $14^{7 x} = 21$ $14 ^(7x) = 21$ ?

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Answer 1 · 2016-05-29T23:09:50

$x = \frac{log (21)}{7 log (14)} \approx 0.1648$ $x = log(21)/(7log(14)) ~~ 0.1648$

Take logs of both sides (any base) to get:

$log (21) = log (14^{7 x}) = 7 x log (14)$ $log(21) = log (14^(7x)) = 7x log(14)$

Divide both ends by $7 log (14)$ $7log(14)$ to find:

$x = \frac{log (21)}{7 log (14)} \approx 0.1648$ $x = log(21)/(7log(14)) ~~ 0.1648$

How do you solve 14 ^(7x) = 21147x=21 14 ^(7x) = 21?