document.write( "Question 410462: please help me solve these equations\r
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document.write( "3log(3y+2) = log(3y+2) - log7\r
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document.write( "and\r
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document.write( "( log(5x-6) / logx ) = 2 \n" );
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Algebra.Com's Answer #288892 by lwsshak3(11628) ![]() You can put this solution on YOUR website! 3log(3y+2) = log(3y+2) - log7 \n" ); document.write( "and( log(5x-6) / logx ) = 2\r \n" ); document.write( "\n" ); document.write( "..\r \n" ); document.write( "\n" ); document.write( "solving second equation, \n" ); document.write( "log(5x-6)/logx=2 \n" ); document.write( "=log(5x-6)=2logx \n" ); document.write( "log(5x-6)-2logx=0 \n" ); document.write( "log(5x-6)/x^2=0 \n" ); document.write( "convert to exponential form, \n" ); document.write( "(5x-6)/x^2=10^0=1 \n" ); document.write( "5x-6=x^2 \n" ); document.write( "x^2-5x+6=0 \n" ); document.write( "(x-3)(x-2)=0 \n" ); document.write( "x-3=0 \n" ); document.write( "x=3 \n" ); document.write( "x-2=0 \n" ); document.write( "x=2 \n" ); document.write( "ans: \n" ); document.write( "x=2 \n" ); document.write( "x=3\r \n" ); document.write( "\n" ); document.write( "..\r \n" ); document.write( "\n" ); document.write( "solving first equation \n" ); document.write( "3log(3y+2)=log(3y+2)-log7 \n" ); document.write( "3log(3y+2)-log(3y+2)+log7=0 \n" ); document.write( "2log(3y+2)+log7=0 \n" ); document.write( "log(3y+2)^2*7)=0 \n" ); document.write( "convert to exponential form, \n" ); document.write( "7(3y+2)^2=10^0=1 \n" ); document.write( "7(9y^2+12y+4)=1 \n" ); document.write( "63y^2+84y+28=1 \n" ); document.write( "63y^2+84y+27=0 \n" ); document.write( "divide by 3 \n" ); document.write( "21y^2+28y+9=0 \n" ); document.write( "solve by quadratic formula, \n" ); document.write( "a=21,b=28,c=9 \n" ); document.write( "y=[-28+-sqrt(28^2-4*21*9)]/2*21 \n" ); document.write( " =[-28+-sqrt(28)]/42 \n" ); document.write( " =(-28+-5.29)/42 \n" ); document.write( "y=-.792 (reject because this makes (3y+2)<0) In logx,x>0 \n" ); document.write( "or \n" ); document.write( "y=-.541\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( " |