How do you solve $5^(x-3) = 21$ ?

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Answer 1 · 2016-04-21T18:00:04

$x=ln21/ln5 +3~~4.89$

$ln 5^(x-3)=ln21$

Use Property $log_bx^n=nlog_bx$

$(x-3) ln5=ln21$

$x-3=ln21/ln5$

$x=ln21/ln5 +3~~4.89$

How do you solve 5^(x-3) = 215^(x-3) = 21?