Ask your own question, for FREE!
Mathematics 22 Online
OpenStudy (anonymous):

Solve.

OpenStudy (anonymous):

\[5^{x - 3} . 3^{2x - 8} = 225 \]

OpenStudy (anonymous):

I think this involves log, but I'm new to it so I would be very grateful if you explain.

OpenStudy (hba):

yeah it does

OpenStudy (hba):

log(a.b)=loga+logb

OpenStudy (hba):

log a^x=xloga

OpenStudy (anonymous):

Yes .... but how does that relate hear?

OpenStudy (anonymous):

sorry here.

OpenStudy (anonymous):

x-3 and 3x-8?

OpenStudy (anonymous):

ok i got it x=5

OpenStudy (anonymous):

I'm still not sure how to proceed ...

OpenStudy (anonymous):

just notice that \[225=15^2=5^2 * 3^2\]

OpenStudy (anonymous):

Yes.

OpenStudy (anonymous):

then x-3=2x-8 and x=5

OpenStudy (shubhamsrg):

altough log would be ideal here but, on slight inspection, you should be easily able to see that: 225 = 5^2 . 3^2 using which you can compare LHS and RHS..

OpenStudy (shubhamsrg):

sorry didnt see @mukushla 's post ;

OpenStudy (anonymous):

|dw:1342104286875:dw|

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!