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

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Answer 1 · 2016-04-21T18:00:04

$x = \frac{ln 21}{ln 5} + 3 \approx 4.89$ $x=ln21/ln5 +3~~4.89$

${ln 5}^{x - 3} = ln 21$ $ln 5^(x-3)=ln21$

Use Property ${log}_{b} x^{n} = n {log}_{b} x$ $log_bx^n=nlog_bx$

$(x - 3) ln 5 = ln 21$ $(x-3) ln5=ln21$

$x - 3 = \frac{ln 21}{ln 5}$ $x-3=ln21/ln5$

$x = \frac{ln 21}{ln 5} + 3 \approx 4.89$ $x=ln21/ln5 +3~~4.89$

How do you solve 5x−3=215^(x-3) = 21?