Solve for t.
\[3^{t+8}=9^{2t}\]
I assume you're covering logarithms?
Yep.
\[3^{t+8}=9^{2t}=\left\{ \left( 3 \right)^2 \right\}^{2t}=3^{4t}\] t+8=4t t=?
something to keep in mind log cancellation rules of \(\bf \large log_{\color{red}{ a}}{\color{red}{ a}}^x\implies x\qquad \qquad {\color{red}{ a}}^{log_{\color{red}{ a}}x}=x\)
I'm not sure how you got there sshayer. However, I converted it to t+8log3=2tlog9
Oh, I see how you got there sshayer. But do you know how to do it with the method where you add log to the equation?
\(\large { 3^{t+8}=9^{2t}\implies 3^{t+8}=(3^2)^{2t}\implies 3^{t+8}=3^{4t} \\ \quad \\ \textit{using the log cancellation rule above} \\ \quad \\ log_{\color{red}{ 3}}\left( {\color{red}{ 3}}^{t+8} \right)=log_{\color{red}{ 3}}\left( {\color{red}{ 3}}^{4t} \right)\implies t+8=4t }\)
solving by log \[3 ^{t+8}=9^{2t}=\left\{ \left( 3 \right) ^2\right\}^{2t}=3^{4t}\] take log of bothsides \[\left( t+8 \right)\log 3=4tlog3\] divide both sides log3 t+8=4t t=?
\[\log~a^x=x~\log~a\]
I get it, thank you!
yw
you could also look at it, the longer way \(\bf log_{\color{red}{ 3}}\left( {\color{red}{ 3}}^{t+8} \right)=log_{\color{red}{ 3}}\left( {\color{red}{ 3}}^{4t} \right)\implies (t+8)(log_3(3))=(4t)(log_3(3)) \\ \quad \\ t+8=\cfrac{4t\cancel{(log_3(3))}}{\cancel{(log_3(3))}}\)
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