document.write( "Question 22743: What is the value of X in the equation: log(x+1) + log
(x-5) = 4 THANK YOU VERY MUCH!!!!! \n" );
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Algebra.Com's Answer #11184 by venugopalramana(3286)![]() ![]() You can put this solution on YOUR website! log \n" ); document.write( "USING THE FORMULA LOG A TO BASE X = LOG A/LOG X TO A COMMON BASE OR STANDARD BASE.HENCE WE HAVE \n" ); document.write( "{LOG (X+1)/LOG 2} + {LOG (X-5)/LOG 2}=4 \n" ); document.write( "LOG(X+1)+LOG(X-5)=4*LOG 2=LOG 2^4=LOG 16 (SINCE LOG X^N=N*LOG X) \n" ); document.write( "LOG(X+1)(X-5)=LOG 16 (SINCE LOG X + LOG Y =LOG(X*Y)) \n" ); document.write( "TAKING ANTILOGS \n" ); document.write( "(X+1)(X-5)=16 \n" ); document.write( "X^2-5X+X-5=16 \n" ); document.write( "X^2-4X-5-16=0 \n" ); document.write( "X^2-7X+3X-21=0 \n" ); document.write( "X(X-7)+3(X-7)=0 \n" ); document.write( "(X-7)(X+3)=0 \n" ); document.write( "HENCE X=7 OR X=-3 AS X=-3 LEADS TO LOG OF NEGATIVE NUMBERS WHICH DO NOT EXIT , THE ANSWER IS X=7 \n" ); document.write( " \n" ); document.write( " |