document.write( "Question 607150: solve log x+log(x+21)=2 \n" ); document.write( "

Algebra.Com's Answer #382441 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( "log x+log(x+21)=2
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document.write( "log x(x+21) = 2
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document.write( "  10^2 = x^2 + 21x
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document.write( "     x^2 + 21x-100 = 0
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document.write( "Factoring***
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document.write( "   (x+25(x-4) = 0
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document.write( "   (x+25) = 0, x = 
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document.write( "    (x-4) = 0, x = 4
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document.write( "Using FOIL to check our Factoring***
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document.write( "F	First terms    x^2
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document.write( "O	Outside terms  -4x
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document.write( "I	Inside terms   +25x 
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document.write( "L	Last terms     -100 \n" );
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