How do you solve $5^{- 9.2 x - 9} - 4 = 57$ $5^(-9.2x-9)-4=57$ ?

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Answer 1 · 2016-11-18T04:49:28

Isolate the term involving the variable, then take the ${log}_{5}$ $log_5$ of both sides.

$5^{- 9.2 x - 9} - 4 = 57$ $5^(-9.2x-9)-4=57$

$5^{- 9.2 x - 9} = 61$ $5^(-9.2x-9)=61$

${log}_{5} (5^{- 9.2 x - 9}) = {log}_{5} 61$ $log_5(5^(-9.2x-9))=log_5 61$

$- 9.2 x - 9 = {log}_{5} 61$ $-9.2x-9=log_5 61$

$- 9.2 x = {log}_{5} 61 + 9$ $-9.2x=log_5 61+9$

$x = - \frac{{log}_{5} 61 + 9}{9.2}$ $x=-(log_5 61+9)/9.2$

$(x \approx - 1.2559)$ $(xapprox-1.2559)$

How do you solve 5−9.2x−9−4=575^(-9.2x-9)-4=57?