document.write( "Question 615686: solve log(x+20)-log(x+2)=logx \n" ); document.write( "
Algebra.Com's Answer #387276 by MathTherapy(10552)![]() ![]() You can put this solution on YOUR website! solve log(x+20)-log(x+2)=logx\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "log (x + 20) - log (x + 2) = log x\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "log \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x(x + 2) = x + 20 ----- Cross-multiplying\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(x + 5)(x - 4) = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x + 5 = 0 or x - 4 = 0\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x = - 5 (EXTRANEOUS) or x = \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "======= \n" ); document.write( "Check \n" ); document.write( "======= \n" ); document.write( "log (x + 20) - log (x + 2) = log x\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "log (4 + 20) - log (4 + 2) = log 4 ------ Substituting 4 for x in original equation\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "log (24) - log (6) = log 4\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "log \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "log (4) = log 4 (TRUE)\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "Send comments and “thank-yous” to “D” at MathMadEzy@aol.com \n" ); document.write( " |