document.write( "Question 104685: Could someone please assist me by solving this logarithmic equation step-by-step for future reference. Thank you.\r
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document.write( "log(7y + 1) = 2log(y+3)-log2\r
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document.write( "log(7y + 1) = log(y+3)^2-log2\r
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document.write( "log(7y + 1) = log(y+3)^2/2
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document.write( "you can write
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document.write( "(7y + 1) = (y+3)^2/2
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document.write( "2(7y + 1) = y^2+6y+9
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document.write( "14y+2=y^2+6y+9
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document.write( "y^2-8y+7=0\r
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document.write( "y1=(8+rootsquare(36))/2
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document.write( " =(8+6)/2
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document.write( " =7
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document.write( "y2=(8-rootsquare(36))/2
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document.write( " =(8-6)/2
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document.write( " =1\r
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document.write( "so (y1,y2) are (7,1) \n" );
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Algebra.Com's Answer #76234 by scott8148(6628)![]() ![]() You can put this solution on YOUR website! handy rules for logs: \n" ); document.write( "adding logs is multiplying numbers \n" ); document.write( "subtracting logs is dividing numbers \n" ); document.write( "multiplying logs is exponentiation \n" ); document.write( "dividing logs is taking roots\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "with those in mind ... 7y+1=((y+3)^2)/2 ... 14y+2=y^2+6y+9\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "y^2-8y+7=0 ... (y-7)(y-1)=0 \n" ); document.write( " |