solve each logarithmic equation. Round your answer to two decimal places.
Teach me this one? I want to work on the next and will submit it once I have it done.
7 log9 (x + 8) = 7


Sagot :

Answer:

[tex]\sf \boxed{\bold{x=1}}[/tex]

Explanation:

[tex]\rightarrow \sf 7 log_9 (x + 8) = 7[/tex]

divide both sides by 7

[tex]\rightarrow \sf \dfrac{7\log _9\left(x+8\right)}{7}=\dfrac{7}{7}[/tex]

simplify the following

[tex]\sf \rightarrow \log _9\left(x+8\right)=1[/tex]

apply log rules                   [tex]\underline{The \ rule}: \ \bold{log_{b} (a)= c} \ \ \Longrightarrow \sf a = b^c[/tex]

[tex]\sf \rightarrow x+8 = 9^1[/tex]

simplify

[tex]\sf \rightarrow x+8=9[/tex]

subtract both sides by 8

[tex]\sf \rightarrow x=1[/tex]

[tex]\\ \rm\Rrightarrow 7log_9(x+8)=7[/tex]

[tex]\\ \rm\Rrightarrow log_9(x+8)=1[/tex]

[tex]\\ \rm\Rrightarrow x+8=9^1[/tex]

  • a^1=a

[tex]\\ \rm\Rrightarrow x+8=9[/tex]

[tex]\\ \rm\Rrightarrow x=9-8[/tex]

[tex]\\ \rm\Rrightarrow x=1[/tex]