Verified Answer :

konrad509

\(D:x-12>0\\ D:x>12\\ \log_3(x-12)=\log_35+2\log_33\\ \log_3(x-12)=\log_35+\log_33^2\\ \log_3(x-12)=\log_35+\log_39\\ \log_3(x-12)=\log_3(9\cdot5)\\ \log_3(x-12)=\log_345\\ x-12=45\\ \boxed{x=57}\)

crisforp

2log 3 = log 3^2 = log 9 ;
log 5 + 2log 3 = log 5 + log 9 = log( 5 * 9 ) = log 45 ;
log ( x - 12 ) = log 45;
x - 12 = 45 ;
x = 12 + 45 ;
x = 57 ;
But, x - 12 > 0;
And, 57 - 12 > 0 ;
The solution is 57 .

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