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9 votes
9 votes
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

User Seymar
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2.3k points

2 Answers

9 votes
9 votes


\\ \rm\Rrightarrow 7log_9(x+8)=7


\\ \rm\Rrightarrow log_9(x+8)=1


\\ \rm\Rrightarrow x+8=9^1

  • a^1=a


\\ \rm\Rrightarrow x+8=9


\\ \rm\Rrightarrow x=9-8


\\ \rm\Rrightarrow x=1

User Ambrosia
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2.8k points
21 votes
21 votes

Answer:


\sf \boxed{\bold{x=1}}

Step-by-step explanation:


\rightarrow \sf 7 log_9 (x + 8) = 7

divide both sides by 7


\rightarrow \sf (7\log _9\left(x+8\right))/(7)=(7)/(7)

simplify the following


\sf \rightarrow \log _9\left(x+8\right)=1

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


\sf \rightarrow x+8 = 9^1

simplify


\sf \rightarrow x+8=9

subtract both sides by 8


\sf \rightarrow x=1

User Lynton Grice
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3.1k points